Java Programming Interview Questions are always the deciding factor in any Java interview. Whether you are a beginner in Java or an expert programmer, you will be tested for your coding skills in the interview. So, it’s a good idea to brush up your coding skills before you face the interview.
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class HelloWorld
{
public static void main(String args[])
{
System.out.println("Hello World!!");
}
}import java.util.Scanner;
class AddNumbers
{
public static void main(String args[])
{
int x, y, z;
System.out.print("Enter two integers to calculate their sum : ");
Scanner in = new Scanner(System.in);
x = in.nextInt();
y = in.nextInt();
z = x + y;
System.out.println("Sum of entered integers = " + z);
}
}class CommandLineArgs
{
public static void main(String args[])
{
int a, b, c;
a = Integer.parseInt(args[0]);
b = Integer.parseInt(args[1]);
c = Integer.parseInt(args[2]);
if (a > b && a > c) {
System.out.println("Largest Number is : " + a);
} else if (b > c) {
System.out.println("Largest Number is : " + b);
} else {
System.out.println("Largest Number is : " + c);
}
}
}class CalculateCircleAreaExample
{
public static void main(String[] args)
{
int radius = 3;
System.out.println("The radius of the circle is " + radius);
/*
* Area of a circle is pi * r * r where r is a radius of a circle.
*/
// NOTE : use Math.PI constant to get value of pi
double area = Math.PI * radius * radius;
System.out.println("Area of a circle is " + area);
}
}import java.util.Scanner;
class AreaOfRectangle
{
public static void main(String[] args)
{
Scanner scanner = new Scanner(System.in);
System.out.println("Enter the length of Rectangle:");
double length = scanner.nextDouble();
System.out.println("Enter the width of Rectangle:");
double width = scanner.nextDouble();
//Area = length*width;
double area = length * width;
System.out.println("Area of Rectangle is:" + area);
}
}import java.util.*;
class AreaOfSquare
{
public static void main(String args[])
{
int side, area;
Scanner sc = new Scanner(System.in);
System.out.println("Enter value of the sides of square");
side = sc.nextInt();
area = side * side;
System.out.println("Area of Square : " + area);
}
}import java.util.Scanner;
class AreaCalculator
{
float l, b, h, r, ba, s, c;
float result = 0f;
float pi = 3.14f;
int var;
public static void main(String[] args)
{
AreaCalculator ar = new AreaCalculator();
ar.options();
}
public void options()
{
Scanner a = new Scanner(System.in);
System.out.println("Enter the Object of which Area is to be calculated \n1:square \n2:rectangle \n3:Triangle\n4:circle\n5:Trapezoid\n6:Repeat\n7:Exit");
var = a.nextInt();
Area a1 = new Area();
if (var == 1)
{
System.out.println("Enter the Side of Square");
s = a.nextFloat();
a1.square(s);
options();
}
else if (var == 2)
{
System.out.println("Enter the Length of Rectangle");
l = a.nextFloat();
System.out.println("Enter the Breadth of Rectangle");
b = a.nextFloat();
a1.rectangle(l, b);
options();
}
else if (var == 3)
{
System.out.println("Enter the Height of Triangle");
h = a.nextFloat();
System.out.println("Enter the Base of Triangle");
ba = a.nextFloat();
a1.triangle(h, ba);
options();
}
else if (var == 4)
{
System.out.println("Enter the Radius of Circle");
r = a.nextFloat();
a1.circle(r);
options();
}
else if (var == 5)
{
System.out.println("Enter the A side of Trapezoid");
b = a.nextFloat();
System.out.println("Enter the B side of Trapezoid");
c = a.nextFloat();
System.out.println("Enter the Height of Trapezoid");
h = a.nextFloat();
a1.trapezoid(b, c, h);
options();
}
}
}
class Area
{
public void square(float s)
{
float result = 0f;
result = s * s;
System.out.println("The Area of Square is :" + result);
}
public void rectangle(float l, float b)
{
float result = 0f;
result = l * b;
System.out.println("The Area of Rectangle is :" + result);
}
public void triangle(float h, float ba)
{
float result = 0f;
result = 0.5f * h * ba;
System.out.println("The Area of Triangle is :" + result);
}
public void circle(float r)
{
float result = 0f;
result = 3.14f * (r * r);
System.out.println("The Area of Circle is :" + result);
}
public void trapezoid(float b, float c, float h)
{
float result = 0f;
result = (((b + c) / 2) * h);
System.out.println("The Area of Trapezoid is :" + result);
}
}import java.lang.*;
import java.util.Scanner;
class CalculateInterest
{
public static void main(String[] args)
{
double p, n, r, si, ci;
Scanner s = new Scanner(System.in);
System.out.print("Enter the amount : ");
p = s.nextDouble();
System.out.print("Enter the No.of years : ");
n = s.nextDouble();
System.out.print("Enter the Rate of interest : ");
r = s.nextDouble();
si = (p * n * r) / 100;
ci = p * Math.pow(1.0 + r / 100.0, n) - p;
System.out.println("\nAmount : " + p);
System.out.println("No. of years : " + n);
System.out.println("Rate of interest : " + r);
System.out.println("Simple Interest : " + si);
System.out.println("Compound Interest : " + ci);
}
}import java.util.*;
class BinaryCalculator
{
public static void main(String[] args)
{
Scanner in = new Scanner(System.in);
System.out.print("First Binary: ");
String binOne = in.next();
System.out.print("Second Binary: ");
String binTwo = in.next();
int left = Integer.parseInt(binOne, 2);
int right = Integer.parseInt(binTwo, 2);
System.out.println("Sum of the binary numbers : " + Integer.toBinaryString(left + right));
System.out.println("Difference of the binary numbers : " + Integer.toBinaryString(left - right));
System.out.println("Product of the binary numbers : " + Integer.toBinaryString(left * right));
System.out.println("Quotient of the binary numbers : " + Integer.toBinaryString(left / right));
}
}import java.util.*;
class CelsiustoFahrenheit
{
public static void main(String[] args)
{
double temperature;
Scanner in = new Scanner(System.in);
System.out.println("Enter temperature in Celsius");
temperature = in.nextInt();
temperature = (temperature * 9 / 5.0) + 32;
System.out.println("Temperature in Fahrenheit = " + temperature);
}
}import java.util.Scanner;
import java.io.*;
class Calculator
{
public static void main(String[] args)
{
int choice;
int x = 0;
int y = 0;
int sum;
PrintStream out;
Scanner input;
Calculator calc = new Calculator();
try
{
out = new PrintStream("calclog.txt");
do
{
System.out.println("Calculator Program"); System.out.println("--------------------\n");
System.out.println("1. Add");
System.out.println("2. Subtract");
System.out.println("3. Multiply");
System.out.println("4. Divide");
System.out.println("5. Mod");
System.out.println("6. Power");
System.out.println("99. End Program\n");
System.out.println("Enter Choice: ");
input = new Scanner(System.in);
choice = input.nextInt();
while ((choice < 1 || choice > 6) && choice != 99)
{
System.out.println("Please enter 1, 2, 3, 4, 5, or 6: ");
choice = input.nextInt();
}
if (choice != 99)
{
System.out.println("Please enter 2 numbers only: ");
x = input.nextInt();
y = input.nextInt();
}
switch (choice)
{
case 1:
sum = calc.add(x, y);
System.out.printf("The sum is %d\n\n", sum);
out.println(x + "+" + y + "=" + sum);
break;
case 2:
sum = calc.sub(x, y);
System.out.printf("The answer is %d\n\n", sum);
out.println(x + "-" + y + "=" + sum);
break;
case 3:
sum = calc.multi(x, y);
System.out.printf("The answer is %d\n\n", sum);
out.println(x + "*" + y + "=" + sum);
break;
case 4:
try
{
sum = calc.div(x, y);
System.out.printf("The answer is %d\n\n", sum);
out.println(x + "/" + y + "=" + sum);
}
catch (Exception e)
{
System.out.println("\nError: Cannot Divide by zero\n\n");
}
break;
case 5:
sum = calc.mod(x, y);
System.out.printf("The mod is %d\n\n", sum);
out.println(x + "%" + y + "=" + sum);
break;
case 6:
sum = calc.pow(x, y)
System.out.printf("The answer is %d\n\n", sum);
out.println(x + "^" + y + "=" + sum);
break;
}
}
while (choice != 99);
input.close();
System.out.println("Ending program...");
}
catch (Exception e){
System.out.println("ERROR: Some error occured");
e.printStackTrace();
}
}
public int add(int num1, int num2)
{int sum;
sum = num1 + num2;
return sum;
}
public int sub(int num1, int num2)
{ int sum;
sum = num1 - num2;
return sum;
}
public int multi(int num1, int num2)
{ int sum;
sum = num1 * num2;
return sum;
}
public int div(int num1, int num2)
{int sum;
sum = num1 / num2;
return sum;
}
public int mod(int num1, int num2)
{int sum;
sum = num1 % num2;
return sum;
}
public int pow(int base, int exp)
{int sum = 1;
if (exp == 0)
{sum = 1;
}
while (exp > 0)
{sum = sum * base;
exp--;
}
return sum;
}
}import java.util.Scanner;
class CalculateMean
{
public static void main(String[] args)
{
int sum = 0, inputNum;
int counter;
float mean;
Scanner NumScanner = new Scanner(System.in);
System.out.println("Enter the total number of terms whose mean you want to calculate");
counter = NumScanner.nextInt();
System.out.println("Please enter " + counter + " numbers:");
for (int x = 1; x <= counter; x++)
{
inputNum = NumScanner.nextInt();
sum = sum + inputNum;
System.out.println();
}
mean = sum / counter;
System.out.println("The mean of the " + counter + " numbers you entered is " + mean);
}
}import java.io.*;
class BinaryToDecimal
{
public static void main(String[] args) throws Exception
{
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
System.out.print("Enter Binary no. to convert in Decimal : ");
String number = br.readLine();
/*
to convert Binary number to decimal number use,
int parseInt method of Integer wrapper class.
Pass 2 as redix second argument.
*/
int decimalNumber = Integer.parseInt(number, 2);
System.out.println("Binary number converted to decimal number");
System.out.println("Decimal number is : " + decimalNumber);
}
}import java.io.*;
class BinaryToOctal
{
public static void main(String[] args) throws Exception
{
String num = null;
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
System.out.print("Enter binary number : ");
num = br.readLine();
int dec = Integer.parseInt(num, 2);
String oct = Integer.toOctalString(dec);
System.out.println("Binary " + num + " in Octal is " + oct);
}
}import java.util.Scanner;
class DecimalToBinary
{
public String toBinary(int n)
{
if (n == 0)
{
return "0";
}
String binary = "";
while (n > 0)
{
int rem = n % 2;
binary = rem + binary;
n = n / 2;
}
return binary;
}
public static void main(String[] args)
{
Scanner scanner = new Scanner(System.in);
System.out.print("Enter a number: ");
int decimal = scanner.nextInt();
DecimalToBinary decimalToBinary = new DecimalToBinary();
String binary = decimalToBinary.toBinary(decimal);
System.out.println("The binary representation is " + binary);
}
}import java.util.*;
class FractionAdding
{
public static void main(String args[])
{
float a, b, c, d;
Scanner scanner = new Scanner(System.in);
System.out.print("Enter a : ");
a = scanner.nextFloat();
System.out.print("Enter b : ");
b = scanner.nextFloat();
System.out.print("Enter c : ");
c = scanner.nextFloat();
System.out.print("Enter d : ");
d = scanner.nextFloat();
// fraction addition formula ((a*d)+(b*c))/(b*d)
System.out.print("Fraction Addition : [( " + a + " * " + d + " )+( " + b + " * " + c + " ) / ( " + b + " * " + d + " )] = " + (((a * d) + (b * c)) / (b * d)));
}
}import java.util.*;
class FractionSubtraction
{
public static void main(String args[])
{
float a,b,c,d;
Scanner scanner = new Scanner(System.in);
System.out.print("Enter a : ");
a = scanner.nextFloat();
System.out.print("Enter b : ");
b = scanner.nextFloat();
System.out.print("Enter c : ");
c = scanner.nextFloat();
System.out.print("Enter d : ");
d = scanner.nextFloat();
// fraction addition formula ((a*d)-(b*c))/(b*d)
System.out.print("Fraction subtraction : [( "+a+" * "+d+" )-( "+b+" * "+c+" ) / ( "+b+" * "+d+" )] = "+(((a*d)-(b*c))/(b*d)));
}
}import java.util.Scanner;
class GCDLCM
{
public static void main(String args[])
{
int x, y;
Scanner sc = new Scanner(System.in);
System.out.println("Enter the two numbers: ");
x = sc.nextInt();
y = sc.nextInt();
System.out.println("GCD of two numbers is : " + gcd(x, y));
System.out.println("LCM of two numbers is : " + lcm(x, y));
}
static int gcd(int x, int y)
{
int r = 0, a, b;
a = (x > y) ? x : y; // a is greater number
b = (x < y) ? x : y; // b is smaller number
r = b;
while (a % b != 0)
{
r = a % b;
a = b;
b = r;
}
return r;
}
static int lcm(int x, int y)
{
int a;
a = (x > y) ? x : y; // a is greater number
while (true)
{
if (a % x == 0 && a % y == 0)
{
return a;
}
++a;
}
}
}import java.util.*;
class HarmonicSeries
{
public static void main(String args[])
{
int num, i = 1;
double rst = 0.0;
Scanner in = new Scanner(System.in);
System.out.println("Enter the number for length of series");
num = in.nextInt();
while (i <= num)
{
System.out.print("1/" + i + " +");
rst = rst + (double) 1 / i;
i++;
}
System.out.println("\n\nSum of Harmonic Series is " + rst);
}
}import java.util.Scanner;
class MultiplicationTable
{
public static void main(String args[])
{
int n, c;
System.out
.println("Enter an integer to print it's multiplication table");
Scanner in = new Scanner(System.in);
n = in.nextInt();
System.out.println("Multiplication table of " + n + " is :-");
for (c = 1; c <= 10; c++)
{
System.out.println(n + "*" + c + " = " + (n * c));
}
}
}A BB CCC DDDD EEEEE
import java.util.*;
class AlphabetPattern
{
public static void main(String[] arg)
{
int line, row, col;
char ch = 'A';
Scanner scanner = new Scanner(System.in);
System.out.print("Enter number of lines : ");
line = scanner.nextInt();
for (row = 1; row <= line; row++)
{
for (col = 1; col <= row; col++)
{
System.out.print("" + ch);
}
System.out.println();
ch++;
}
}
}1 01 101 0101 10101
class BinaryPattern
{
public static void main(String s[])
{
int i, j;
int count = 1;
for (i = 1; i <= 5; i++)
{
for (j = 1; j <= i; j++)
{
System.out.format("%d", count++ % 2);
if (j == i && i != 5)
System.out.println("");
}
if (i % 2 == 0)
count = 1;
else
count = 0;
}
}
}class ChristmasTree
{
public static final int segments = 4;
public static final int height = 4;
public static void main(String[] args)
{
makeTree();
}
public static void makeTree()
{
int maxStars = 2 * height + 2 * segments - 3;
String maxStr = "";
for (int l = 0; l < maxStars; l++)
{
maxStr += " ";
}
for (int i = 1; i <= segments; i++)
{
for (int line = 1; line <= height; line++)
{
String starStr = "";
for (int j = 1; j <= 2 * line + 2 * i - 3; j++)
{
starStr += "*";
}
for (int space = 0; space <= maxStars - (height + line + i); space++)
{
starStr = " " + starStr;
}
System.out.println(starStr);
}
}
for (int i = 0; i <= maxStars / 2; i++)
{
System.out.print(" ");
}
System.out.println(" " + "*" + " ");
for (int i = 0; i <= maxStars / 2; i++)
{
System.out.print(" ");
}
System.out.println(" " + "*" + " ");
for (int i = 0; i <= maxStars / 2 - 3; i++)
{
System.out.print(" ");
}
System.out.println(" " + "*******");
}
} X
X
XXX
X
XXXXX
X
XXX
XXXXXX
class ChristmasTreePattern
{
public static void main(String[] arg)
{
drawChristmasTree(4);
}
private static void drawChristmasTree(int n)
{
for (int i = 0; i < n; i++)
{
triangle(i + 1, n);
}
}
private static void triangle(int n, int max)
{
for (int i = 0; i < n; i++)
{
for (int j = 0; j < max - i - 1; j++)
{
System.out.print(" ");
}
for (int j = 0; j < i * 2 + 1; j++)
{
System.out.print("X");
}
System.out.println("");
}
}
}1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
import java.util.Scanner;
class FloydTriangle
{
public static void main(String args[])
{
int n, num = 1, c, d;
Scanner in = new Scanner(System.in);
System.out.print("Enter the number of rows of floyd's triangle : ");
n = in.nextInt();
System.out.println("Floyd's triangle :-");
for (c = 1; c <= n; c++)
{
for (d = 1; d <= c; d++)
{
System.out.print(num + " ");
num++;
}
System.out.println();
}
}
}1 12 123 1234 12345
class NumberPat1
{
public static void main(String arg[])
{
for (int i = 1; i <= 5; i++)
{
for (int j = 1; j <= i; j++)
{
System.out.print(j);
}
System.out.println();
}
}
}class NumberPat2
{
public static void main(String arg[])
{
for (int i = 1; i <= 5; i++)
{
for (int j = 5; j >= i; j--)
{
System.out.print(j);
}
System.out.println();
}
}
}12345 1234 123 12 1
class NumberPat3
{
public static void main(String arg[])
{
for (int i = 1, r = 5; i <= 5; i++, r--)
{
for (int j = 1; j <= r; j++)
{
System.out.print(j);
}
System.out.println();
}
}
}1 12 123 1234 12345 1234 123 12 1
class NumberPat4
{
public static void main(String arg[])
{
int ck = 0, c = 2;
while (c > 0)
{
if (ck == 0)
{
for (int i = 1; i <= 5; i++)
{
for (int j = 1; j <= i; j++)
{
System.out.print(j);
}
System.out.println();
}
ck++;
}
else
{
for (int i = 1, r = 5 - 1; i <= 5 - 1; i++, r--)
{
for (int j = 1; j <= r; j++)
{
System.out.print(j);
}
System.out.println();
}
}
c--;
}
}
}12345 1234 123 12 1 12 123 1234 12345
class NumberPat5
{
public static void main(String arg[])
{
int ck = 0, c = 2;
while (c > 0)
{
if (ck == 0)
{
for (int i = 1, r = 5; i <= 5; i++, r--)
{
for (int j = 1; j <= r; j++)
{
System.out.print(j);
}
System.out.println();
}
ck++;
}
else
{
for (int i = 2; i <= 5; i++)
{
for (int j = 1; j <= i; j++)
{
System.out.print(j);
}
System.out.println();
}
}
c--;
}
}
}1 22 333 4444 55555
class NumberPat6
{
public static void main(String arg[])
{
for(int i=1;i<=5;i++)
{
for(int j=1;j<=i;j++)
{
System.out.print(i);
}
System.out.println();
}
}
}1 23 456 7890 12345
class NumberPat7
{
public static void main(String arg[])
{
int t = 1;
for (int i = 1; i <= 5; i++)
{
for (int j = 1; j <= i; j++)
{
if (t == 10)
t = 0;
System.out.print(t++);
}
System.out.println();
}
}
}5 11111 0000 111 00 1
import java.util.Scanner;
class Pattern
{
public static void main(String args[])
{
int n, i, j;
Scanner sc = new Scanner(System.in);
System.out.println("Enter the number of rows ");
n = sc.nextInt();
for (i = 1; i <= n; i++)
{
for (j = i; j <= n; j++)
{
if (i % 2 == 0)
System.out.print("0");
else
System.out.print("1");
}
System.out.println();
}
}
} 1
1 2 1
1 2 3 2 1
1 2 3 4 3 2 1
1 2 3 4 5 4 3 2 1
class PrintPattern
{
public static void main(String args[])
{
int n = 5;
for (int i = 1; i <= n; i++)
{
int j = n - i;
while (j > 0)
{
System.out.print(" ");
j--;
}
j = 1;
while (j <= i)
{
System.out.print(" " + j);
j++;
}
j = i - 1;
while (j > 0)
{
System.out.print(" " + j);
j--;
}
j = n - i;
while (j > 0)
{
System.out.print(" ");
j--;
}
System.out.println();
}
}
}1 121 12321 1234321 123454321 12345654321 1234567654321
import java.util.*;
class Pattern
{
public static void main(String[] args)
{
int i, j, k = 1, l, n;
Scanner sc = new Scanner(System.in);
System.out.println("Enter the number of levels of pattern");
n = sc.nextInt();
System.out.println("\nPattern is : \n");
for (i = 1; i <= n; i++)
{
l = i;
for (j = 1; j <= k; j++)
{
if (j >= i + 1)
{
System.out.print(--l);
}
else
{
System.out.print(j);
}
}
k = k + 2;
System.out.println(" ");
}
}
}**** *** ** *
class StarPattern1
{
public static void main(String arg[])
{
for (int i = 1; i <= 5; i++)
{
for (int j = i; j <= 5; j++)
{
System.out.print("*");
}
System.out.println();
}
}
}* ** *** **** *****
class StarPattern2
{
public static void main(String arg[])
{
for (int i = 1; i <= 5; i++)
{
for (int j = 1; j <= i; j++)
{
System.out.print("*");
}
System.out.println();
}
}
}***** **** *** ** * * ** *** **** *****
class StarPattern3
{
public static void main(String arg[])
{
for (int i = 1; i <= 5; i++)
{
for (int j = i; j <= 5; j++)
{
System.out.print("*");
}
System.out.println();
}
for (int i = 1; i <= 5; i++)
{
for (int j = 1; j <= i; j++)
{
System.out.print("*");
}
System.out.println();
}
}
}** **** ****** ******** **********
class StarPattern4
{
public static void main(String arg[])
{
int num = 12;
int f = 2;
int g = num - 1;
for (int i = 1; i <= (num / 2); i++)
{
for (int j = 1; j <= num; j++)
{
if (j >= f && j <= g)
{
System.out.print(" ");
}
else
{
System.out.print("*");
}
}
f = f + 1;
g = g - 1;
System.out.println();
}
}
}* ** *** **** ***** ***** **** *** ** *
class StarPattern5
{
public static void main(String arg[])
{
for (int i = 1; i <= 5; i++)
{
for (int j = 1; j <= i; j++)
{
System.out.print("*");
}
System.out.println();
}
for (int i = 1; i <= 5; i++)
{
for (int j = i; j <= 5; j++)
{
System.out.print("*");
}
System.out.println();
}
}
}import java.io.*;
class Triangle
{
public static void main(String arg[])
{
InputStreamReader istream = new InputStreamReader(System.in);
BufferedReader read = new BufferedReader(istream);
System.out.println("Enter Triangle Size : ");
int num = 0;
try
{
num = Integer.parseInt(read.readLine());
}
catch (Exception Number)
{
System.out.println("Invalid Number!");
}
for (int i = 1; i <= num; i++)
{
for (int j = 1; j < num - (i - 1); j++)
{
System.out.print(" ");
}
for (int k = 1; k <= i; k++)
{
System.out.print("*");
for (int k1 = 1; k1 < k; k1 += k)
{
System.out.print("*");
}
}
System.out.println();
}
}
}import java.util.*;
class AddTwoMatrix
{
int m, n;
int first[][] = new int[m][n];
int second[][] = new int[m][n];
AddTwoMatrix(int[][] first, int[][] second, int m, int n)
{
this.first = first;
this.second = second;
this.m = m;
this.n = n;
}
public static void main(String[] args)
{
int m, n, c, d;
Scanner in = new Scanner(System.in);
System.out.println("Enter the number of rows and columns of matrix");
m = in.nextInt();
n = in.nextInt();
int first[][] = new int[m][n];
int second[][] = new int[m][n];
System.out.println("Enter the elements of first matrix");
for (c = 0; c < m; c++)
{
for (d = 0; d < n; d++)
{
first[c][d] = in.nextInt();
}
}
System.out.println("Enter the elements of second matrix");
for (c = 0; c < m; c++)
{
for (d = 0; d < n; d++)
{
second[c][d] = in.nextInt();
}
}
System.out.println("\nElements of First matrix is : ");
for (c = 0; c < m; c++)
{
for (d = 0; d < n; d++)
{
System.out.print(first[c][d] + "\t");
}
System.out.println();
}
System.out.println("\nElements of Second matrix is : ");
for (c = 0; c < m; c++)
{
for (d = 0; d < n; d++)
{
System.out.print(second[c][d] + "\t");
}
System.out.println();
}
AddTwoMatrix a = new AddTwoMatrix(first, second, m, n);
//call by reference
a.addmatrix(a); //Passing Object
}
//Function for Adding two matrix and storing in third matrix
public void addmatrix(AddTwoMatrix a)
{
int c, d;
int sum[][] = new int[a.m][a.n];
for (c = 0; c < a.m; c++)
{
for (d = 0; d < a.n; d++)
{
sum[c][d] = a.first[c][d] + a.second[c][d];
}
}
System.out.println("\nSum of the two matrices is : ");
for (c = 0; c < a.m; c++)
{
for (d = 0; d < a.n; d++)
{
System.out.print(sum[c][d] + "\t");
}
System.out.println();
}
}
}class ArrayOfArraysAnimalDemo
{
public static void main(String[] args)
{
String[][] animals = {{"DanaDog", "WallyDog", "JessieDog", "AlexisDog", "LuckyDog"}, {"BibsCat", "DoodleCat", "MillieCat", "SimonCat"}, {"ElyFish", "CloieFish", "GoldieFish", "OscarFish", "ZippyFish", "TedFish"}, {"RascalMule", "GeorgeMule", "GracieMule", "MontyMule", "BuckMule", "RosieMule"}};
for (int i = 0; i < animals.length; i++)
{
System.out.print(animals[i][0] + ": ");
for (int j = 1; j < animals[i].length; j++)
{
System.out.print(animals[i][j] + " ");
}
System.out.println();
}
}
}class ArrayOperations
{
public static void main(String[] args)
{
double[] myList = {1.9, 2.9, 3.4, 3.5};
// Print all the array elements
for (int i = 0; i < myList.length; i++)
{
System.out.println(myList[i] + " ");
}
// Summing all elements
double total = 0;
for (int i = 0; i < myList.length; i++)
{
total += myList[i];
}
System.out.println("Total is " + total);
// Finding the largest element
double max = myList[0];
for (int i = 1; i < myList.length; i++)
{
if (myList[i] > max)
max = myList[i];
}
System.out.println("Max is " + max);
}
}import java.util.Arrays;
class ArraySort
{
// This program is the example of array sorting
public static void main(String[] args)
{
// TODO Auto-generated method stub
// initializing unsorted array
String iArr[] = {"Programming", "Hub", "Alice", "Wonder", "Land"};
// sorting array
Arrays.sort(iArr);
// let us print all the elements available in list
System.out.println("The sorted array is:");
for (int i = 0; i < iArr.length; i++)
{
System.out.println(iArr[i]);
}
}
}import java.io.*;
class ArrayAverage
{
public static void main(String[] args)
{
//define an array
int[] numbers = new int[]{10, 20, 15, 25, 16, 60, 100};
int sum = 0;
for (int i = 0; i < numbers.length; i++)
{
sum = sum + numbers[i];
}
double average = sum / numbers.length;
System.out.println("Sum of array elements is : " + sum);
System.out.println("Average value of array elements is : " + average);
}
}import java.util.*;
class ArrayBasic
{
public static void main(String[] args)
{
int[] arr;
int size, i;
Scanner sc = new Scanner(System.in);
System.out.println("Enter size of array");
size = sc.nextInt();
arr = new int[size];
System.out.println("\nEnter array elements");
for (i = 0; i < size; i++)
{
arr[i] = sc.nextInt();
}
System.out.println("\nElements in the Array are : ");
for (i = 0; i < size; i++)
{
System.out.print(arr[i] + " ");
}
}
}import java.util.Scanner;
class Matrix_Create {
Scanner scan;
int matrix[][];
int row, column;
void create() {
scan = new Scanner(System.in);
System.out.println("Matrix Creation");
System.out.println("\nEnter number of rows :");
row = Integer.parseInt(scan.nextLine());
System.out.println("Enter number of columns :");
column = Integer.parseInt(scan.nextLine());
matrix = new int[row][column];
System.out.println("Enter the data :");
for(int i=0; i<row ; i++) {
for(int j=0; j
<column ; j++) {
matrix[i][j] =scan.nextInt();
}
}
}
void display() {
System.out.println("\nThe Matrix is :");
for(int i=0; i <row ; i++) {
for(int j=0; j <column ; j++) {
System.out.print("\t" + matrix[i][j]);
}
System.out.println();
}
}
}
class CreateAndDisplayMatrix {
public static void main(String
args[]) {
Matrix_Create obj=new Matrix_Create();
obj.create();
obj.display();
}
}class DisplayArrayForEach
{
public static void main(String[] args)
{
double[] myList = {1.9, 2.9, 3.4, 3.5};
// Print all the array elements
for (double element : myList)
{
System.out.println(element);
}
}
}import java.util.*;
import java.text.DecimalFormat;
class DoubleMatrix
{
public static void main(String[] args)
{
double[][] a;
double[] s;
int row, col, k = 0, i, j;
double sum = 0.0;
DecimalFormat f = new DecimalFormat("##.####");
Scanner sc = new Scanner(System.in);
System.out.println("Enter size of row and column");
row = sc.nextInt();
col = sc.nextInt();
a = new double[row][col];
s = new double[col];
System.out.println("Enter elements of matrix");
for (i = 0; i < row; i++)
{
for (j = 0; j < col; j++)
{
a[i][j] = sc.nextDouble();
}
}
System.out.println("Double Matrix is : ");
for (i = 0; i < row; i++)
{
for (j = 0; j < col; j++)
{
System.out.print(" " + a[i][j]);
}
System.out.println();
}
//sum of the elements of double matrix
for (i = 0; i < col; i++)
{
for (j = 0; j < row; j++)
{
sum = sum + a[j][i];
}
s[k] = sum;
k++;
sum = 0;
}
for (i = 0; i < col; i++)
{
System.out.println("Sum of Column " + (i + 1) + " is : " + f.format(s[i]));
}
}
}import java.util.*;
class PassingArraystoFunction
{
public static void main(String[] args)
{
int[] a;
int size;
Scanner sc = new Scanner(System.in);
System.out.println("Enter size of array");
size = sc.nextInt();
a = new int[size];
System.out.println("Enter elements in the array");
for(int i = 0 ;i < size; i++)
{
a[i] = sc.nextInt();
}
System.out.println("The Elements of the array are : ");
for(int i = 0 ;i < size; i++)
{
System.out.print(a[i] + " ");
}
//Passing array to the function
addElements(a, size);
}
public static void addElements(int[] a , int size)
{
int sum = 0;
for(int i = 0; i < size; i++)
{
sum += a[i];
}
System.out.println("\nSum of the elements of arrays is : "+sum);
}
}import java.util.*;
class ClosestValue
{
public static void main(String[] args)
{
int a[];
int find;
int closest = 0;
Scanner sc = new Scanner(System.in);
System.out.println("Enter size of array");
int size = sc.nextInt();
a = new int[size];
System.out.println("Enter numbers in array");
for (int i = 0; i < size; i++)
{
a[i] = sc.nextInt();
}
System.out.println("Numbers are : ");
for (int i = 0; i < size; i++)
{
System.out.print(a[i] + " ");
}
System.out.println();
System.out.println("Enter Number to find closest value");
find = sc.nextInt();
int distance = Math.abs(closest - find);
for (int i : a)
{
int distanceI = Math.abs(i - find);
if (distance > distanceI)
{
closest = i;
distance = distanceI;
}
}
System.out.println("Closest Value is : " + closest);
}
}import java.io.*;
class MagicMatrix
{
public static void main(String args[]) throws IOException
{
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
System.out.print("Enter the size of the matrix : ");
int n = Integer.parseInt(br.readLine());
if (n > 5)
System.out.println("Enter a number between 1 to 5 ");
else
{
int A[][] = new int[n][n]; // Creating the Magic Matrix
int i, j, k, t;
/*Initializing every cell of the matrix with 0 */
for (i = 0; i < n; i++)
{
for (j = 0; j < n; j++)
{
A[i][j] = 0;
}
}
/* When the size of the matrix is Odd */
if (n % 2 != 0)
{
i = 0;
j = n / 2;
k = 1;
while (k <= n * n)
{
A[i][j] = k++;
i--; // Making one step upward
j++; // Moving one step to the right
if (i < 0 && j > n - 1) // Condition for the top-right corner element
{
i = i + 2;
j--;
}
if (i < 0) // Wrapping around the row if it goes out of boundary
i = n - 1;
if (j > n - 1) // Wrapping around the column if it goes out of boundary
j = 0;
if (A[i][j] > 0) // Condition when the cell is already filled
{
i = i + 2;
j--;
}
}
}
/* When the size of the matrix is even */
else
{
k = 1;
/* Filling the matrix with natural numbers from 1 till n*n */
for (i = 0; i < n; i++)
{
for (j = 0; j < n; j++)
{
A[i][j] = k++;
}
}
j = n - 1;
for (i = 0; i < n / 2; i++)
{
/* swapping corner elements of primary diagonal */
t = A[i][i];
A[i][i] = A[j][j];
A[j][j] = t;
/* swapping corner elements of secondary diagonal */
t = A[i][j];
A[i][j] = A[j][i];
A[j][i] = t;
j--;
}
}
/* Printing the Magic matrix */
System.out.println("The Magic Matrix of size " + n + "x" + n + " is:");
for (i = 0; i < n; i++)
{
for (j = 0; j < n; j++)
{
System.out.print(A[i][j] + "\t");
}
System.out.println();
}
}
}
}import java.util.Scanner;
class MatrixAddition {
Scanner scan;
int matrix1[][], matrix2[][], sum[][];
int row, column;
void create() {
scan = new Scanner(System.in);
System.out.println("Matrix Addition");
// First Matrix Creation..
System.out.println("\nEnter number of rows & columns");
row = Integer.parseInt(scan.nextLine());
column = Integer.parseInt(scan.nextLine());
matrix1 = new int[row][column];
matrix2 = new int[row][column];
sum = new int[row][column];
System.out.println("Enter the data for first matrix :");
for(int i=0; i < row; i++) {
for(int j=0; j < column; j++) {
matrix1[i][j] = scan.nextInt();
}
}
// Second Matrix Creation..
System.out.println("Enter the data for second matrix :");
for(int i=0; i < row; i++) {
for(int j=0; j < column; j++) {
matrix2[i][j] = scan.nextInt();
}
}
}
void display() {
System.out.println("\nThe First Matrix is :");
for(int i=0; i < row; i++) {
for(int j=0; j < column; j++) {
System.out.print("\t" + matrix1[i][j]);
}
System.out.println();
}
System.out.println("\n\nThe Second Matrix is :");
for(int i=0; i < row; i++) {
for(int j=0; j < column; j++) {
System.out.print("\t" + matrix2[i][j]);
}
System.out.println();
}
}
void add() {
for(int i=0; i < row; i++) {
for(int j=0; j < column; j++) {
sum[i][j] = matrix1[i][j] + matrix2[i][j];
}
}
System.out.println("\n\nThe Sum is :");
for(int i=0; i < row; i++) {
for(int j=0; j < column; j++) {
System.out.print("\t" + sum[i][j]);
}
System.out.println();
}
}
}
class MatrixAdditionExample {
public static void main(String args[]) {
MatrixAddition obj = new MatrixAddition();
obj.create();
obj.display();
obj.add();
}
}import java.util.Scanner;
class MatrixMultiplication
{
public static void main(String args[])
{
int m, n, p, q, sum = 0, c, d, k;
Scanner in = new Scanner(System.in);
System.out.println("Enter the number of rows and columns of first matrix");
m = in.nextInt();
n = in.nextInt();
int first[][] = new int[m][n];
System.out.println("Enter the elements of first matrix");
for (c = 0; c < m; c++)
{
for (d = 0; d < n; d++)
{
first[c][d] = in.nextInt();
}
}
System.out.println("Enter the number of rows and columns of second matrix");
p = in.nextInt();
q = in.nextInt();
if (n != p)
System.out.println("Matrices with entered orders can't be multiplied with each other.");
else
{
int second[][] = new int[p][q];
int multiply[][] = new int[m][q];
System.out.println("Enter the elements of second matrix");
for (c = 0; c < p; c++)
{
for (d = 0; d < q; d++)
{
second[c][d] = in.nextInt();
}
}
for (c = 0; c < m; c++)
{
for (d = 0; d < q; d++)
{
for (k = 0; k < p; k++)
{
sum = sum + first[c][k] * second[k][d];
}
multiply[c][d] = sum;
sum = 0;
}
}
System.out.println("Product of entered matrices:-");
for (c = 0; c < m; c++)
{
for (d = 0; d < q; d++)
{
System.out.print(multiply[c][d] + "\t");
}
System.out.print("\n");
}
}
}
}import java.util.Scanner;
public class Matrices {
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
System.out.print("Enter number of rows: ");
int rows = scanner.nextInt();
System.out.print("Enter number of columns: ");
int columns = scanner.nextInt();
System.out.println();
System.out.println("Enter first matrix");
int[][] a = readMatrix(rows, columns);
System.out.println();
System.out.println("Enter second matrix");
int[][] b = readMatrix(rows, columns);
int[][] sum = add(a, b);
int[][] difference1 = subtract(a, b);
int[][] difference2 = subtract(b, a);
System.out.println();
System.out.println("A + B =");
printMatrix(sum);
System.out.println();
System.out.println("A - B =");
printMatrix(difference1);
System.out.println();
System.out.println("B - A =");
printMatrix(difference2);
}
public static int[][] readMatrix(int rows, int columns) {
int[][] result = new int[rows][columns];
Scanner s = new Scanner(System.in);
for (int i = 0; i < rows; i++) {
for (int j = 0; j < columns; j++) {
result[i][j] = s.nextInt();
}
}
return result;
}
public static int[][] add(int[][] a, int[][] b) {
int rows = a.length;
int columns = a[0].length;
int[][] result = new int[rows][columns];
for (int i = 0; i < rows; i++) {
for (int j = 0; j < columns; j++) {
result[i][j] = a[i][j] + b[i][j];
}
}
return result;
}
public static int[][] subtract(int[][] a, int[][] b) {
int rows = a.length;
int columns = a[0].length;
int[][] result = new int[rows][columns];
for (int i = 0; i < rows; i++) {
for (int j = 0; j < columns; j++) {
result[i][j] = a[i][j] - b[i][j];
}
}
return result;
}
public static void printMatrix(int[][] matrix) {
int rows = matrix.length;
int columns = matrix[0].length;
for (int i = 0; i < rows; i++) {
for (int j = 0; j < columns; j++) {
System.out.print(matrix[i][j] + " ");
}
System.out.println();
}
}
}import java.util.Scanner;
class Matrix_Subtraction {
Scanner scan;
int matrix1[][], matrix2[][], sub[][];
int row, column;
void create() {
scan = new Scanner(System.in);
System.out.println("Matrix Subtraction");
// First Matrix Creation..
System.out.println("\nEnter number of rows & columns");
row = Integer.parseInt(scan.nextLine());
column = Integer.parseInt(scan.nextLine());
matrix1 = new int[row][column];
matrix2 = new int[row][column];
sub = new int[row][column];
System.out.println("Enter the data for first matrix :");
for(int i=0; i < row; i++) {
for(int j=0; j < column; j++) {
matrix1[i][j] = scan.nextInt();
}
}
// Second Matrix Creation..
System.out.println("Enter the data for second matrix :");
for(int i=0; i < row; i++) {
for(int j=0; j < column; j++) {
matrix2[i][j] = scan.nextInt();
}
}
}
void display() {
System.out.println("\nThe First Matrix is :");
for(int i=0; i < row; i++) {
for(int j=0; j < column; j++) {
System.out.print("\t" + matrix1[i][j]);
}
System.out.println();
}
System.out.println("\n\nThe Second Matrix is :");
for(int i=0; i < row; i++) {
for(int j=0; j < column; j++) {
System.out.print("\t" + matrix2[i][j]);
}
System.out.println();
}
}
void sub() {
for(int i=0; i < row; i++) {
for(int j=0; j < column; j++) {
sub[i][j] = matrix1[i][j] - matrix2[i][j];
}
}
System.out.println("\n\nThe Subtraction is :");
for(int i=0; i < row; i++) {
for(int j=0; j < column; j++) {
System.out.print("\t" + sub[i][j]);
}
System.out.println();
}
}
}
class MatrixSubtractionExample {
public static void main(String args[]) {
Matrix_Subtraction obj = new Matrix_Subtraction();
obj.create();
obj.display();
obj.sub();
}
}class MergeArrayDemo
{
public static void main(String args[])
{
Integer a[]={1,2,3,4};
Integer b[]={5,6,7,0};
Integer[] both = concat(a, b);
System.out.print("\nFirst Array : ");
for(int i=0;i<a.length;i++)
{
System.out.print(a[i]+"\t");
}
System.out.print("\nSecond Array : ");
for(int i=0;i<b.length;i++)
{
System.out.print(b[i]+"\t");
}
System.out.print("\nMerged Array : ");
for(int i=0;i<both.length;i++)
{
System.out.print(both[i]+"\t");
}
}
public static Integer[] concat(Integer[] a, Integer[] b)
{
int aLen = a.length;
int bLen = b.length;
Integer[] c= new Integer[aLen+bLen];
System.arraycopy(a, 0, c, 0, aLen);
System.arraycopy(b, 0, c, aLen, bLen);
return c;
}
}import java.util.*;
class MiddleValue
{
public static void main(String args[])
{
int[] a;
int i, j, n, sum = 0, swap, size;
double t;
Scanner sc = new Scanner(System.in);
System.out.println("Enter size of array");
size = sc.nextInt();
a = new int[size];
System.out.println("Enter numbers ");
for (i = 0; i < size; i++)
{
a[i] = sc.nextInt();
}
System.out.println("Numbers are : ");
for (i = 0; i < size; i++)
{
System.out.print(a[i] + " ");
}
//Sorting
for (i = 0; i < (size - 1); i++)
{
for (j = 0; j < (size - i - 1); j++)
{
if (a[j] > a[j + 1])
{
swap = a[j];
a[j] = a[j + 1];
a[j + 1] = swap;
}
}
}
System.out.println("\nNumbers in sorted order : ");
for (i = 0; i < size; i++)
{
System.out.print(a[i] + " ");
}
//Finding the Middle Value
if (size % 2 == 0)
{
n = (size + 1) / 2;
t = (a[n] + a[n - 1]) / 2.0;
System.out.println("\nMiddle Value is : " + t);
}
else
{
System.out.println("\nMiddle Value is : " + a[size / 2]);
}
}
}import java.util.*;
class MirrorMatrix
{
public static void main(String[] args)
{
int row, column;
Scanner in = new Scanner(System.in);
System.out.print("Enter number of rows for matrix :");
row = in.nextInt();
System.out.print("Enter number of rows for matrix :");
column = in.nextInt();
int matrix[][] = new int[row][column];
System.out.println("Enter matrix : ");
for (int i = 0; i < row; i++)
{
for (int j = 0; j < column; j++)
{
matrix[i][j] = in.nextInt();
}
}
System.out.println("Mirror matrix : ");
for (int i = 0; i < row; i++)
{
for (int j = column - 1; j >= 0; j--)
{
System.out.print(matrix[i][j] + "\t");
}
System.out.println("");
}
}
}class MissingNumberArray
{
public static int count = 0;
public static int position = 0;
public static boolean flag = false;
public static void main(String[] args)
{
int a[] = {0, 1, 2, 3, 4, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 18, 20, 21, 23};
findMissingNumbers(a, position);
}
private static void findMissingNumbers(int a[], int position)
{
if (position == a.length - 1)
return;
for (; position < a[a.length - 1]; position++)
{
if ((a[position] - count) != position)
{
System.out.println("Missing Number: " + (position + count));
flag = true;
count++;
break;
}
}
if (flag)
{
flag = false;
findMissingNumbers(a, position);
}
}
}class MultiDimArrayExample
{
public static void main(String[] args)
{
String[][] names = {{"Mr. ", "Mrs. ", "Ms. "}, {"Smith", "Jones"}};
// Mr. Smith
System.out.println(names[0][0] + names[1][0]);
// Ms. Jones
System.out.println(names[0][2] + names[1][1]);
}
}