Language: Java

import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Comparator;
import java.util.LinkedList;
import java.util.List;
import java.util.NoSuchElementException;
import java.util.PriorityQueue;
import java.util.ArrayDeque;
import java.util.Queue;
class Edge{
    int to;
    long cost;
    Edge(int to,long cost){
        this.to = to;
        this.cost = cost;
    }
}

public class Main {
    public static void main(String[] args) {
        FastScanner fs = new FastScanner();
        int a = fs.nextInt();
        int b = fs.nextInt();
      	
        System.out.println(a*b);
}
static void dfs(int v) {
		vis[v] = true;
		boolean last = true;
		long wt = 1, bt = 1;
		for(int to:graph[v]) {
			if(vis[to]==true)continue;
			last = false;
			dfs(to);
			wt = mul(wt, plus(dp[to][0], dp[to][1]));
			bt = mul(bt, dp[to][0]);
		}
		if(last) {
			dp[v][0] = 1;
			dp[v][1] = 1;
		}
		else {
			dp[v][0] = wt;
			dp[v][1] = bt;
		}
		return;
	}
}
class ModCalc {
  //MOD culculations
static long plus(long x, long y) {
  x %= mod;
  y %= mod;
  long res = (x + y) % mod;
  return res;
}

static long sub(long x, long y) {
  x %= mod;
  y %= mod;
  long res = (x - y + mod) % mod;
  return res;
}

static long mul(long x, long y) {
  x %= mod;
  y %= mod;
  long res = x * y % mod;
  return res;
}

static long div(long x, long y) {
  x %= mod;
  y %= mod;
  long res = x * modpow(y, mod - 2) % mod;
  return res;
}

//modの元での高速pow()
static long modpow(long a, long p) {
  if (p == 0)
    return 1;
  if (p % 2 == 0) {
    long halfP = p / 2;
    long root = modpow(a, halfP);
    return root * root % mod;
  } else
    return a * modpow(a, p - 1) % mod;
}
}
class FastScanner {
    private final InputStream in = System.in;
    private final byte[] buffer = new byte[1024];
    private int ptr = 0;
    private int buflen = 0;
    private boolean hasNextByte(){
        if(ptr < buflen){
            return true;
        }else{
            ptr = 0;
            try{
                buflen = in.read(buffer);
            }catch(IOException e){
                e.printStackTrace();
            }
            if(buflen <=0){
                return false;
            }
        }
        return true;
    }

    private int readByte(){
        if(hasNextByte())return buffer[ptr++];
        else return -1;
    }

    private static boolean isPrintableChar(int c){
        return 33<=c && c<=126;
    }
    public boolean hasNext(){
        while(hasNextByte() && !isPrintableChar(buffer[ptr]))ptr++;
        return hasNextByte();
    }

    public String next(){
        if(!hasNext()) throw new NoSuchElementException();
        StringBuilder sb = new StringBuilder();
        int b = readByte();
        while(isPrintableChar(b)){
            sb.appendCodePoint(b);
            b = readByte();
        }
        return sb.toString();
    }

    public long nextLong(){
        if(!hasNext()) throw new NoSuchElementException();
        long n = 0;
        boolean minus = false;
        int b = readByte();
        if(b == '-'){
            minus = true;
            b = readByte();
        }
        if(b < '0' || '9' < b){
            throw new NumberFormatException();
        }
        while(true){
            if('0' <= b && b<='9'){
                n*=10;
                n+=b-'0';
            }else if(b==-1 || !isPrintableChar(b)){
                return minus ? -n : n;
            }else{
                throw new NumberFormatException();
            }
            b = readByte();
        }
    }
    public int nextInt(){
        long nl = nextLong();
        if(nl < Integer.MIN_VALUE || nl > Integer.MAX_VALUE)throw new NumberFormatException();
        return (int) nl;
    }
    public double nextDoutble(){return Double.parseDouble(next());}
}


Compiler output:
Main.java:30: error: cannot find symbol
		vis[v] = true;
		^
  symbol:   variable vis
  location: class Main
Main.java:33: error: cannot find symbol
		for(int to:graph[v]) {
		           ^
  symbol:   variable graph
  location: class Main
Main.java:34: error: cannot find symbol
			if(vis[to]==true)continue;
			   ^
  symbol:   variable vis
  location: class Main
Main.java:37: error: cannot find symbol
			wt = mul(wt, plus(dp[to][0], dp[to][1]));
			                  ^
  symbol:   variable dp
  location: class Main
Main.java:37: error: cannot find symbol
			wt = mul(wt, plus(dp[to][0], dp[to][1]));
			                             ^
  symbol:   variable dp
  location: class Main
Main.java:38: error: cannot find symbol
			bt = mul(bt, dp[to][0]);
			             ^
  symbol:   variable dp
  location: class Main
Main.java:41: error: cannot find symbol
			dp[v][0] = 1;
			^
  symbol:   variable dp
  location: class Main
Main.java:42: error: cannot find symbol
			dp[v][1] = 1;
			^
  symbol:   variable dp
  location: class Main
Main.java:45: error: cannot find symbol
			dp[v][0] = wt;
			^
  symbol:   variable dp
  location: class Main
Main.java:46: error: cannot find symbol
			dp[v][1] = bt;
			^
  symbol:   variable dp
  location: class Main
Main.java:54: error: cannot find symbol
  x %= mod;
       ^
  symbol:   variable mod
  location: class ModCalc
Main.java:55: error: cannot find symbol
  y %= mod;
       ^
  symbol:   variable mod
  location: class ModCalc
Main.java:56: error: cannot find symbol
  long res = (x + y) % mod;
                       ^
  symbol:   variable mod
  location: class ModCalc
Main.java:61: error: cannot find symbol
  x %= mod;
       ^
  symbol:   variable mod
  location: class ModCalc
Main.java:62: error: cannot find symbol
  y %= mod;
       ^
  symbol:   variable mod
  location: class ModCalc
Main.java:63: error: cannot find symbol
  long res = (x - y + mod) % mod;
                      ^
  symbol:   variable mod
  location: class ModCalc
Main.java:63: error: cannot find symbol
  long res = (x - y + mod) % mod;
                             ^
  symbol:   variable mod
  location: class ModCalc
Main.java:68: error: cannot find symbol
  x %= mod;
       ^
  symbol:   variable mod
  location: class ModCalc
Main.java:69: error: cannot find symbol
  y %= mod;
       ^
  symbol:   variable mod
  location: class ModCalc
Main.java:70: error: cannot find symbol
  long res = x * y % mod;
                     ^
  symbol:   variable mod
  location: class ModCalc
Main.java:75: error: cannot find symbol
  x %= mod;
       ^
  symbol:   variable mod
  location: class ModCalc
Main.java:76: error: cannot find symbol
  y %= mod;
       ^
  symbol:   variable mod
  location: class ModCalc
Main.java:77: error: cannot find symbol
  long res = x * modpow(y, mod - 2) % mod;
                           ^
  symbol:   variable mod
  location: class ModCalc
Main.java:77: error: cannot find symbol
  long res = x * modpow(y, mod - 2) % mod;
                                      ^
  symbol:   variable mod
  location: class ModCalc
Main.java:88: error: cannot find symbol
    return root * root % mod;
                         ^
  symbol:   variable mod
  location: class ModCalc
Main.java:90: error: cannot find symbol
    return a * modpow(a, p - 1) % mod;
                                  ^
  symbol:   variable mod
  location: class ModCalc
26 errors