Competitive programming code snippet for java users. Feel free to clone/fork/copy.
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Install Visual Studio Code, and set up JDK.
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Go to
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Paste below key-value's into
java.json
"Template for codeforces CP" : {
"prefix": "cft",
"body":[
"import java.util.*;",
"import java.io.*;",
"public class Main {",
"private static final FastScanner sc = new FastScanner();",
"private static void solve() {",
"$0",
"}",
"static class FastScanner {",
"BufferedReader br;",
"StringTokenizer st;",
"public FastScanner() {",
"try {",
"br = new BufferedReader(new FileReader(\"input.txt\"));",
"PrintStream out = new PrintStream(new FileOutputStream(\"output.txt\"));",
"System.setOut(out);",
"} catch(Exception e) {",
"br = new BufferedReader(new InputStreamReader(System.in));",
"}",
"}",
"String next() {",
"while (st == null || !st.hasMoreElements()) {",
"try {",
"st = new StringTokenizer(br.readLine());",
"} catch (IOException e) {",
"e.printStackTrace();",
"}",
"}",
"return st.nextToken();",
"}",
"String nextLine() {",
"String str = \"\";",
"try {",
"str = br.readLine();",
"} catch (IOException e) {",
"e.printStackTrace();",
"}",
"return str;",
"}",
"int nextInt() { return Integer.parseInt(next()); }",
"long nextLong() { return Long.parseLong(next()); }",
"double nextDouble() { return Double.parseDouble(next()); }",
"}",
"public static void main(String[] args) {",
"int T = sc.nextInt();",
"for (int t = 1; t <= T; ++t) {",
"if (t > 1) System.out.println();",
"solve();",
"}",
"}",
"}"
],
"description": "template for codeforces cp in java"
},
"Template for baekjoon online judge CP" : {
"prefix": "bojt",
"body":[
"import java.util.*;",
"import java.io.*;",
"public class Main {",
"private static final FastScanner sc = new FastScanner();",
"private static void solve() {",
"$0",
"}",
"static class FastScanner {",
"BufferedReader br;",
"StringTokenizer st;",
"public FastScanner() {",
"try {",
"br = new BufferedReader(new FileReader(\"input.txt\"));",
"PrintStream out = new PrintStream(new FileOutputStream(\"output.txt\"));",
"System.setOut(out);",
"} catch(Exception e) {",
"br = new BufferedReader(new InputStreamReader(System.in));",
"}",
"}",
"String next() {",
"while (st == null || !st.hasMoreElements()) {",
"try {",
"st = new StringTokenizer(br.readLine());",
"} catch (IOException e) {",
"e.printStackTrace();",
"}",
"}",
"return st.nextToken();",
"}",
"String nextLine() {",
"String str = \"\";",
"try {",
"str = br.readLine();",
"} catch (IOException e) {",
"e.printStackTrace();",
"}",
"return str;",
"}",
"int nextInt() { return Integer.parseInt(next()); }",
"long nextLong() { return Long.parseLong(next()); }",
"double nextDouble() { return Double.parseDouble(next()); }",
"}",
"public static void main(String[] args) {",
"int T = sc.nextInt();",
"for (int t = 1; t <= T; ++t) {",
"if (t > 1) System.out.println();",
"System.out.print(\"Case #\" + t + \": \");",
"solve();",
"}",
"}",
"}"
],
"description": "template for baekjoon online judge cp in java"
},
"For loop i": {
"prefix": "fori",
"body": [
"for (int i= 0; i < $0; ++i)"
],
"description": "simple for loop"
},
"For loop j": {
"prefix": "forj",
"body": [
"for (int j= 0; j < $0; ++j)"
],
"description": "simple for loop"
},
"For loop k": {
"prefix": "fork",
"body": [
"for (int k= 0; k < $0; ++k)"
],
"description": "simple for loop"
},
"For loop l": {
"prefix": "forl",
"body": [
"for (int l= 0; l < $0; ++l)"
],
"description": "simple for loop"
},
"Print": {
"prefix": "print",
"body": [
"System.out.print($0);"
],
"description": "simple print method"
},
"Print Line": {
"prefix": "printl",
"body": [
"System.out.println($0);"
],
"description": "simple print line method"
},
"Union Find": {
"prefix": "unionfind",
"body": [
"static class UnionFind {",
"int[] group;",
"UnionFind(int n) {",
"group= new int[n+1];",
"for (int i=1; i <= n; ++i) {",
"group[i]= i;",
"}",
"}",
"int find(int i) {",
"if (group[i] == i) return i;",
"return group[i]= find(group[i]);",
"}",
"void union(int a, int b) {",
"group[b]= find(a);",
"}",
"}"
]
},
"Next Permutation": {
"prefix": "permu",
"body": [
"static class Permu {",
"int[] nextPermutation(int[] arr) {",
"int n = arr.length;",
"int[] ret = new int[n];",
"for (int i = 0; i < n; ++i)",
"ret[i] = arr[i];",
"int pivot = n - 1;",
"while (pivot > 0 && ret[pivot - 1] >= ret[pivot])",
"--pivot;",
"if (pivot > 0) {",
"--pivot;",
"int idx = n - 1;",
"while (ret[idx] <= ret[pivot])",
"--idx;",
"swap(ret, pivot, idx);",
"reverse(ret, pivot + 1, n - 1);",
"} else {",
"Arrays.sort(ret);",
"}",
"return ret;",
"}",
"void swap(int[] arr, int a, int b) {",
"int tmp = arr[a];",
"arr[a] = arr[b];",
"arr[b] = tmp;",
"}",
"void reverse(int[] arr, int l, int r) {",
"int[] buf = new int[r - l + 1];",
"for (int i = l; i <= r; ++i)",
"buf[i - l] = arr[r - (i - l)];",
"for (int i = 0; i < r - l + 1; ++i)",
"arr[l + i] = buf[i];",
"}",
"}"
],
"description": "next permutation implementation in java"
},
"Trie": {
"prefix": "trie",
"body": [
"static class TrieNode {",
"char val;",
"boolean exist;",
"Map<Character, TrieNode> children;",
"TrieNode(char val) {",
"this.val = val;",
"children = new HashMap<>();",
"}",
"char getVal() {",
"return val;",
"}",
"void setVal(char val) {",
"this.val = val;",
"}",
"void addChild(TrieNode node) {",
"children.put(node.getVal(), node);",
"}",
"TrieNode getChild(char c) {",
"return children.get(c);",
"}",
"boolean findWord(String word) {",
"if (word.length() == 0)",
"return exist;",
"if (!children.containsKey(word.charAt(0)))",
"return false;",
"return children.get(word.charAt(0)).findWord(word.substring(1));",
"}",
"void addWord(String word) {",
"if (word.length() == 0) {",
"exist = true;",
"return;",
"}",
"TrieNode child = children.get(word.charAt(0));",
"if (child == null) {",
"addChild(new TrieNode(word.charAt(0)));",
"child = children.get(word.charAt(0));",
"}",
"child.addWord(word.substring(1));",
"}",
"}"
],
"description": "trie data structure"
},
"Prime Utils": {
"prefix": "primeutil",
"body": [
"static class PrimeUtil {",
"static Map<Integer, List<Integer>> factors(int upTo) {",
"Map<Integer, List<Integer>> p = new HashMap<>();",
"p.put(1, new ArrayList<>());",
"for (int i = 2; i <= upTo; ++i) {",
"if (!p.containsKey(i)) {",
"for (int j = i; j <= upTo; j += i) {",
"p.computeIfAbsent(j, primes -> new ArrayList<>()).add(i);",
"}",
"}",
"}",
"return p;",
"}",
"static int countPrimeFactors(long num) {",
"if (num == 1) return 0;",
"int cnt= 0;",
"for (int i=2; i*i <= num; ++i) {",
"if (num%i == 0) {",
"++cnt;",
"while (num%i == 0) num /= i;",
"}",
"}",
"return num > 1 ? cnt+1 : cnt;",
"}",
"static boolean isPrime(long num) {",
"return countPrimeFactors(num) == 1;",
"}",
"}"
],
"description": "factorization using sieve of Eratosthenes"
},
"Modular Utils": {
"prefix": "modutil",
"body": [
"private static final int MOD= (int)1e9+7;",
"private static int _add(int a, int b) { return (int)((a+0L+b)%MOD); }",
"private static int _mul(int a, int b) { return (int)(a*1L*b%MOD); }",
"private static int _inv(int a) { return binEx(a, MOD-2); }",
"private static int _div(int a, int b) { return _mul(a, _inv(b)); }",
"private static int binEx(int a, int x) {",
"if (x == 0) return 1;",
"int p= binEx(a, x>>1);",
"p= _mul(p, p);",
"return (x&1) == 1 ? _mul(p,a) : p;",
"}"
],
"description": "modular embedded basic operations"
},
"Number Utils": {
"prefix": "numberutil",
"body": [
"private static int gcd(int a, int b) {",
"if (a < b) return gcd(b,a);",
"while (b > 0) {",
"int tmp= a%b;",
"a= b;",
"b= tmp;",
"}",
"return a;",
"}",
"private static int lcm(int a, int b) {",
"return (int)(a*1L*b/gcd(a,b));",
"}"
]
},
"KMP Algorithm": {
"prefix": "kmp",
"body": [
"static class Kmp {",
"int n;",
"char[] p;",
"int[] lps;",
"Kmp(String pattern) {",
"n= pattern.length();",
"p= pattern.toCharArray();",
"lps= new int[n];",
"int len= 0, i= 1;",
"while (i < n) {",
"if (p[len] == p[i]) {",
"lps[i++]= ++len;",
"} else {",
"if (len > 0) {",
"len= lps[len-1];",
"} else {",
"lps[i++]= 0;",
"}",
"}",
"}",
"}",
"List<Integer> getMatchIndices(String text) {",
"List<Integer> ret= new ArrayList<>();",
"int i= 0, len= 0;",
"while (i < text.length()) {",
"if (len == n) {",
"ret.add(i-n);",
"len= lps[len-1];",
"continue;",
"}",
"if (text.charAt(i) == p[len]) {",
"++i;",
"++len;",
"} else {",
"if (len > 0) len= lps[len-1];",
"else ++i;",
"}",
"}",
"if (len == n) ret.add(i-n);",
"return ret;",
"}",
"}"
],
"description": "kmp algorithm class"
}- Try to use snippet inside the editor. Make sure you format the whole content.
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alt+shift+F
prefix: "cft"
import java.util.*;
import java.io.*;
public class Main {
private static final FastScanner sc = new FastScanner();
private static void solve() {
}
static class FastScanner {
BufferedReader br;
StringTokenizer st;
public FastScanner() {
try {
br = new BufferedReader(new FileReader("input.txt"));
PrintStream out = new PrintStream(new FileOutputStream("output.txt"));
System.setOut(out);
} catch (Exception e) {
br = new BufferedReader(new InputStreamReader(System.in));
}
}
String next() {
while (st == null || !st.hasMoreElements()) {
try {
st = new StringTokenizer(br.readLine());
} catch (IOException e) {
e.printStackTrace();
}
}
return st.nextToken();
}
String nextLine() {
String str = "";
try {
str = br.readLine();
} catch (IOException e) {
e.printStackTrace();
}
return str;
}
int nextInt() {
return Integer.parseInt(next());
}
long nextLong() {
return Long.parseLong(next());
}
double nextDouble() {
return Double.parseDouble(next());
}
}
public static void main(String[] args) {
int T = sc.nextInt();
for (int t = 1; t <= T; ++t) {
if (t > 1)
System.out.println();
solve();
}
}
}prefix: "bojt"
import java.util.*;
import java.io.*;
public class Main {
private static final FastScanner sc = new FastScanner();
private static void solve() {
}
static class FastScanner {
BufferedReader br;
StringTokenizer st;
public FastScanner() {
try {
br = new BufferedReader(new FileReader("input.txt"));
PrintStream out = new PrintStream(new FileOutputStream("output.txt"));
System.setOut(out);
} catch (Exception e) {
br = new BufferedReader(new InputStreamReader(System.in));
}
}
String next() {
while (st == null || !st.hasMoreElements()) {
try {
st = new StringTokenizer(br.readLine());
} catch (IOException e) {
e.printStackTrace();
}
}
return st.nextToken();
}
String nextLine() {
String str = "";
try {
str = br.readLine();
} catch (IOException e) {
e.printStackTrace();
}
return str;
}
int nextInt() {
return Integer.parseInt(next());
}
long nextLong() {
return Long.parseLong(next());
}
double nextDouble() {
return Double.parseDouble(next());
}
}
public static void main(String[] args) {
int T = sc.nextInt();
for (int t = 1; t <= T; ++t) {
if (t > 1)
System.out.println();
System.out.print("Case #" + t + ": ");
solve();
}
}
}