Merge branch 'master' into master

Author: Bhrigu Kansra

24 hr.py

@@ -0,0 +1,19 @@
+
+def convert24(str1): 
+      
+    if str1[-2:] == "AM" and str1[:2] == "12": 
+        return "00" + str1[2:-2] 
+          
+        
+    elif str1[-2:] == "AM": 
+        return str1[:-2] 
+        elif str1[-2:] == "PM" and str1[:2] == "12": 
+        return str1[:-2] 
+          
+    else: 
+      
+        return str(int(str1[:2]) + 12) + str1[2:8] 
+           
+
+str1=input("enter time")
+print(convert24("str1"))

Algorithms/Dynamic Programming/C++/knapsack.cpp

@@ -0,0 +1,43 @@
+#include <bits/stdc++.h>
+using namespace std;
+#define ll long long
+#define o 100005
+#define MOD 1000000007
+#define pb push_back
+#define mp make_pair
+#define mem(a,b) memset(a,(b),sizeof(a))
+#define lpo(a) for(int i=0;i<a;i++)
+#define loop(a,x) for(int i=a;i<x;i++)
+#define srt(x) sort(x.begin(),x.end())
+#define all(x) x.begin(),x.end()
+const ll MAX=1000000000000000001;
+typedef pair<int,int> pii;
+int knapSack(int W, int wt[], int val[], int n) 
+{ 
+   int i, w; 
+   int K[n+1][W+1]; 
+   for (i = 0; i <= n; i++) 
+   { 
+       for (w = 0; w <= W; w++) 
+       { 
+           if (i==0 || w==0) 
+               K[i][w] = 0; 
+           else if (wt[i-1] <= w) 
+                 K[i][w] = max(val[i-1] + K[i-1][w-wt[i-1]],  K[i-1][w]); 
+           else
+                 K[i][w] = K[i-1][w]; 
+       } 
+   } 
+  
+   return K[n][W]; 
+} 
+  
+int main() 
+{ 
+    int val[] = {20, 30, 40}; 
+    int wt[] = {10, 20, 30}; 
+    int  W = 50; 
+    int n = sizeof(val)/sizeof(val[0]); 
+    cout<<knapSack(W, wt, val, n); 
+    return 0; 
+} 

Algorithms/Recursion/C++/nqueens.cpp

@@ -0,0 +1,38 @@
+
+
+#define N 4 
+#include<stdio.h> 
+#include<stdbool.h> 
+  
+void printSolution(int board[N][N]) 
+{ 
+    for (int i = 0; i < N; i++) 
+    { 
+        for (int j = 0; j < N; j++) 
+            printf(" %d ", board[i][j]); 
+        printf("\n"); 
+    } 
+} 
+  
+
+bool isSafe(int board[N][N], int row, int col) 
+{ 
+    int i, j; 
+  
+    /* Check this row on left side */
+    for (i = 0; i < col; i++) 
+        if (board[row][i]) 
+            return false; 
+  
+    /* Check upper diagonal on left side */
+    for (i=row, j=col; i>=0 && j>=0; i--, j--) 
+        if (board[i][j]) 
+            return false; 
+  
+    /* Check lower diagonal on left side */
+    for (i=row, j=col; j>=0 && i<N; i++, j--) 
+        if (board[i][j]) 
+            return false; 
+  
+    return true; 
+} 

Algorithms/Recursion/C++/recursion.cpp

@@ -0,0 +1,23 @@
+
+
+#include<bits/stdc++.h> 
+using namespace std; 
+  
+void printFun(int test) 
+{ 
+    if (test < 1) 
+        return; 
+    else
+    { 
+        cout << test << " "; 
+        printFun(test-1);    // statement 2 
+        cout << test << " "; 
+        return; 
+    } 
+} 
+  
+int main() 
+{ 
+    int test = 3; 
+    printFun(test); 
+} 

Algorithms/Recursion/Python/recursion.py

@@ -0,0 +1,17 @@
+
+
+  
+def printFun(test): 
+  
+    if (test < 1): 
+        return
+    else: 
+      
+        print( test,end = " ") 
+        printFun(test-1) # statement 2 
+        print( test,end = " ") 
+        return
+      
+  
+test = 3
+printFun(test)

contributors.md

@@ -42,4 +42,6 @@
 40. [Riya Singh](https://github.com/riya24899)
 41. [Sarthak gupta](https://github.com/sarthak-g)
 42. [Nitish Kumar](https://github.com/nitish14kumr)
-43. [Your Name](https://github.com/yourusername)
+43. [Seemant Aggarwal] (https://github.com/seemantaggarwal)
+44. [Vibhav Tiwari] (https://github.com/VibhavTiwari)
+45. [Your Name](https://github.com/yourusername)

math/C++/determinant.cpp

@@ -0,0 +1,29 @@
+#define N 4
+#include <bits/stdc++.h> 
+using namespace std; 
+  
+
+void getCofactor(int mat[N][N], int temp[N][N], int p, int q, int n) 
+{ 
+    int i = 0, j = 0; 
+  
+    
+    for (int row = 0; row < n; row++) 
+    { 
+        for (int col = 0; col < n; col++) 
+        { 
+          
+            if (row != p && col != q) 
+            { 
+                temp[i][j++] = mat[row][col]; 
+  
+            
+                if (j == n - 1) 
+                { 
+                    j = 0; 
+                    i++; 
+                } 
+            } 
+        } 
+    } 
+} 

math/C++/prime number.cpp

@@ -0,0 +1,26 @@
+#include <iostream>
+using namespace std;
+
+int main()
+{
+  int n, i;
+  bool isPrime = true;
+
+  cout << "Enter a positive integer: ";
+  cin >> n;
+
+  for(i = 2; i <= n / 2; ++i)
+  {
+      if(n % i == 0)
+      {
+          isPrime = false;
+          break;
+      }
+  }
+  if (isPrime)
+      cout << "This is a prime number";
+  else
+      cout << "This is not a prime number";
+
+  return 0;
+}

math/Python/prime number.py

@@ -0,0 +1,20 @@
+num = 407
+
+# take input from the user
+# num = int(input("Enter a number: "))
+
+# prime numbers are greater than 1
+if num > 1:
+   # check for factors
+   for i in range(2,num):
+       if (num % i) == 0:
+           print(num,"is not a prime number")
+           print(i,"times",num//i,"is",num)
+           break
+   else:
+       print(num,"is a prime number")
+       
+# if input number is less than
+# or equal to 1, it is not prime
+else:
+   print(num,"is not a prime number")