criyle/codenet-compile-errors huggingface dataset:
Language: Java

import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int N = Integer.parseInt(sc.next());
        String S1 = sc.next();
        String S2 = sc.next();
        int mod = 1_000_000_007;
        long ans = 1;
        int flag = -1; // flag==0: yoko, flag==1: tate
        for (int i=0;i<N;i++) {
            if (i==0) {
                if (i!=N-1 && S1.charAt(i)==S1.charAt(i+1)) {  //yoko
                    ans = 6;
                    i++;
                    flag=0;
                } else {
                    ans = 3;
                    flag=1;
                }
            }
            if (flag==0) { // yoko
                if (i!=N-1 && S1.charAt(i)==S1.charAt(i+1)) { // yoko
                    ans = ans*3%mod;
                    i++;
                } else { // tate
                    flag=1;
                }
            } else { // tate
                if (i!=N-1 && S1.charAt(i)==S1.charAt(i+1)) { // yoko
                    ans = ans*2%mod;
                    flag=0;
                    i++;
                } else { // yoko
                    ans = ans*2%mod
                }
            }
        }
        System.out.println(ans);
    }
}

Compiler output:
Main.java:36: error: ';' expected
                    ans = ans*2%mod
                                   ^
1 error
Language: C++

#include<iostream>
#include<sstream>
#include<fstream>
#include<cstring>/*The header <string> and
<string.h> does not contain the useful
function 'memset' and 'memcpy'.*/
#include<vector>
#include<stack>
#include<map>
#include<set>
#include<queue>
#include<deque>
#include<bitset>
#include<utility>
#include<algorithm>
#include<functional>
#include<ctime>
#include<cmath>
#include<cstdlib>
#include<cstdio>
using namespace std;
map<char,int> mp;
char S[2][55];
vector<char> v;
vector<char> G[256];
const long long modulo=1000000007;
int main()
{
	int N;
	cin>>N;
	cin>>S[0]>>S[1];
	for(int i=0;i<strlen(S[0]);i++)
	{
		v.push_back(S[0][i]);
		if(i<strlen(S[0])-1&&S[0][i]==S[0][i+1])
			i++,
			v.push_back(S[1][i]);
	}
	for(int str=0;str<1;str++)
		for(int i=0;i<strlen(S[str]);i++)
			if(i<strlen(S[str])-1&&S[str][i]==S[str][i+1])
			{
				G[S[1][i]].push_back(S[0][i]);
				i++;
			}
	for(int str=0;str<2;str++)
		for(int i=0;i<strlen(S[str])-1;i++)
			if(S[str][i]!=S[str][i+1])
				G[S[str][i+1]].push_back(S[str][i]);
	for(int i=0;i<v.size();i++)
		ans*=3-G[v[i]].size(),
		ans%=modulo;
	cout<<ans<<endl;
	return 0;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:51:17: error: 'ans' was not declared in this scope; did you mean 'abs'?
   51 |                 ans*=3-G[v[i]].size(),
      |                 ^~~
      |                 abs
a.cc:53:15: error: 'ans' was not declared in this scope; did you mean 'abs'?
   53 |         cout<<ans<<endl;
      |               ^~~
      |               abs
Language: C++

#include <bits/stdc++.h>
using namespace std;

long long 1000000007=1000000007ll;
int n,pos;
string S1,S2;

int main()
{
	cin>>n>>S1>>S2;
	long long ans;
	bool v;
	if(S1[0]==S2[0])
	{
		ans=3;
		pos++;
		v=true;
	}
	else
	{
		ans=6;
		pos+=2;
		v=false;
	}
	while(pos<n)
	{
		if(S1[pos]==S2[pos])
		{
			if(v)
				ans*=2;
			pos++;
			v=true;
		}
		else
		{
			if(v)
				ans*=2;
			else 
				ans*=3;
			pos+=2;
			v=false;
		}
		if(ans>=1000000007)
			ans%=1000000007;
	}
	cout << ans << endl;
	return 0;
}


Compiler output:
a.cc:4:11: error: expected unqualified-id before numeric constant
    4 | long long 1000000007=1000000007ll;
      |           ^~~~~~~~~~
Language: C++

#include<bits/stdc++.h>
using namespace std;

#define _overload3(_1,_2,_3,name,...) name
#define _rep(i,n) repi(i,0,n)
#define repi(i,a,b) for(int i=int(a);i<int(b);++i)
#define rep(...) _overload3(__VA_ARGS__,repi,_rep,)(__VA_ARGS__)

const int mod=1000000007;

int main(){
  int n;
  cin>>n;
  string s1,s2;
  cin>>s1;
  cin>>s2;
  ll ans;
  bool prev=0;
  if(s1[0]==s2[0]){
    ans=3;
    rep(i,1,n){
      if(s1[i]==s2[i]&&s1[i-1]==s2[i-1]){
        ans*=2;
        ans%=mod;
      }
      if(s1[i]==s2[i]&&s1[i-1]!=s2[i-1]){
        ans%=mod;
      }
      if(s1[i]!=s2[i]&&s1[i-1]==s2[i-1]){
        ans*=2;
        ans%=mod;
        ++i;
      }
      if(s1[i]!=s2[i]&&s1[i-1]!=s2[i-1]){
        ans*=3;
        ans%=mod;
        ++i;
      }
    }
  }
  else{
    ans=6;
    rep(i,2,n){
      if(s1[i]==s2[i]&&s1[i-1]==s2[i-1]){
        ans*=2;
        ans%=mod;
      }
      if(s1[i]==s2[i]&&s1[i-1]!=s2[i-1]){
        ans%=mod;
      }
      if(s1[i]!=s2[i]&&s1[i-1]==s2[i-1]){
        ans*=2;
        ans%=mod;
        ++i;
      }
      if(s1[i]!=s2[i]&&s1[i-1]!=s2[i-1]){
        ans*=3;
        ans%=mod;
        ++i;
      }
    }
  }
  cout<<ans<<endl;
}
      
      
  

Compiler output:
a.cc: In function 'int main()':
a.cc:17:3: error: 'll' was not declared in this scope
   17 |   ll ans;
      |   ^~
a.cc:20:5: error: 'ans' was not declared in this scope; did you mean 'abs'?
   20 |     ans=3;
      |     ^~~
      |     abs
a.cc:42:5: error: 'ans' was not declared in this scope; did you mean 'abs'?
   42 |     ans=6;
      |     ^~~
      |     abs
a.cc:63:9: error: 'ans' was not declared in this scope; did you mean 'abs'?
   63 |   cout<<ans<<endl;
      |         ^~~
      |         abs
Language: C++

#include <vector>
#include <list>
#include <map>
#include <set>
#include <deque>
#include <stack>
#include <bitset>
#include <algorithm>
#include <functional>
#include <numeric>
#include <utility>
#include <sstream>
#include <iostream>
#include <iomanip>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <cctype>
#include <string>
#include <cstring>
#include <ctime>
#include <queue>
#include<climits>
using namespace std;

#define MOD 1000000007
#define INF LONG_MAX

int main(){
  int n;
  string S[2];
  cin >> n;
  cin >> S[0];
  cin >> S[1];
  bool pattern,prevPattern;
  long long ans ;
  for(int i = 0; i < S[0].size(); i++){
    if(i+1 < S[0].size() && S[0][i] == S[0][i+1]){
      pattern = true;
      i++;
    }else{
      pattern = false;
    }
    if((!pattern && i == 0) || (pattern && i == 1)){
      if(pattern) ans = 6;
      else        ans = 3;
      prevPattern = pattern;
      continue;
    }else{
      if(!prevPattern){
        ans = ans * 2 % MOD;
      }else if(prevPattern && patter){
        ans = ans * 3 % MOD;
      }
      prevPattern = pattern;
    }
  }
  cout << ans << endl;
  return 0;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:52:31: error: 'patter' was not declared in this scope; did you mean 'pattern'?
   52 |       }else if(prevPattern && patter){
      |                               ^~~~~~
      |                               pattern
Language: C++

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

#define MOD (1000000007ll)
int main(void){
	int n,i,a=3,b=6,ft=0,b[55];
	ll ans=1ll;
	char s[2][55];
	cin >> n >> s[0] >> s[1];
	for(i=0; i<n; i++){
		if(s[0][i] == s[1][i]){
			switch(ft){
				case 0:
					ans *= 3;
					break;
				case 1:
					ans *= 2;
					break;
				case 2:
					ans *= 1;
					break;
				default:
					break;
			}
			ft = 1;
			ans %= MOD;
		}else{
			switch(ft){
				case 0:
					ans *= 6;
					break;
				case 1:
				case 2:
					ans *= 2;
					break;
				default:
					break;
			}
			i++;
			ft = 2;
			ans %= MOD;
		}
	}
	cout << ans << endl;
	return 0;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:9:30: error: conflicting declaration 'int b [55]'
    9 |         int n,i,a=3,b=6,ft=0,b[55];
      |                              ^
a.cc:9:21: note: previous declaration as 'int b'
    9 |         int n,i,a=3,b=6,ft=0,b[55];
      |                     ^
Language: C++

#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <cstring>
#include <climits>
#include <vector>
#include <map>
#include <set>
#include <list>
#include <stack>
#include <queue>
#include <algorithm>
#include <iostream>
#include <string>

#define REP(i,n) for(int i=0;i<n;++i)
#define REPR(i,n) for(int i=n;i>=0;--i)
#define REPI(itr,v) for(auto itr=v.begin();itr!=v.end();++itr)
#define REPIR(itr,v) for(auto itr=v.rbegin();itr!=v.rend();++itr)
#define FOR(i,a,b) for(int i=a;i<b;++i)
#define SORT(v,n) sort(v, v+n)
#define SORTV(v) sort(v.begin(), v.end())
#define ALL(v) v.begin(),v.end()
#define llong long long
#define INF 999999999
#define SUR 1000000007
#define pb(a) push_back(a)
#define pf(a) push_front(a)
#define MP make_pair

int dx[] = {0, 0, -1, 1};
int dy[] = {1, -1, 0, 0};

using namespace std;

typedef pair<int,int> pii;

int main(){

  int n;

  string s1, s2;
  cin >> n >> s1 >> s2;

  llong ans;
  if(s1[0] == s2[0]){
    ans = 3;
    bool len = true;

    FOR(i,1,n){
      if(s1[i] == s2[i]){
        if(len){
          len = true;
          ans = (ans * 2) % SUR;
        }else{
          len =true;
          continue;
        }
      }else{
        if(len){
          i++;
          ans = (ans * 2) % SUR;
          len = false;
          continue;
        }else{
          i++;
          ans = (ans * 3) % SUR;
          len = false;
        }
      }
    }
  }else{
    bool len = false;
    ans = 6;
    FOR(i,2,n){
      if(s1[i] == s2[i]){
        if(len){
          len = true;
          ans = (ans * 2) % SUR;
        }else{
          len =true;
          continue;
        }
      }else{
        if(len){
          i++;
          ans = (ans * 2) % SUR/
          len =false;
          continue;
        }else{
          i++;
          ans = (ans * 3) % SUR;
        }
      }
    }
  }

  cout << ans << "\n";
  return 0;
}



Compiler output:
a.cc: In function 'int main()':
a.cc:87:32: error: lvalue required as left operand of assignment
   87 |           ans = (ans * 2) % SUR/
      |                 ~~~~~~~~~~~~~~~^
   88 |           len =false;
      |           ~~~
Language: Java

import java.util.*;

public class Main {
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        String s1 = sc.next();
        String s2 = sc.next();

        String VH = "";
        for (int i=0; i<n; i++) {
            if (s1.charAt(i) == s2.charAt(i)) {
                VH += "V";
            } else {
                VH += "H"; i++;
            }
        }
        //System.out.println(VH);

        long total = 3;
        if (VH.charAt(0) == 'H') {
            total *= 2;
        }
        int m;
        for (int i=1; i<VH.length(); i++) {
            if (VH.charAt(i) == 'H') {
                if (VH.charAt(i-1) == 'H') {
                    m = 3;
                } else {
                    m = 2;
                }
            } else {
                if (VH.charAt(i-1) == 'H') {
                    m = 1;
                } else {
                    m = 2;
                }
            }
            //System.out.println(total + " x " + m);
            total *= m;
        }
        System.out.println(total % 1000000007);
        }
    }
}


Compiler output:
Main.java:45: error: class, interface, enum, or record expected
}
^
1 error
Language: C++

#include<iostream>
#include<string>
#define value( x ) 
cout<< "value of "<< #x << " is "<< x<<endl;
long long max( long long x, long long y) 
{
if(x>y) return x;else return y;}using namespace std;
const long long mod = 1000000007;
int main(){	    
long long n;   
cin>>n;    
string a,b;    
cin>>a>>b;   
int ppos=-1, pppos=-1, ptype=0,pptype=0;   
long long answare=0;
 for(int i=0;i<n;i++)  {    	if(a[i]!=b[i]){    		
 if(ptype==1) answare=(answare*2)%mod;    		
 else if(ptype==2) answare=(answare*3)%mod;    		
 else answare=6;   		
 ptype=2;    		
 i++;}    	
 else    	
 {   		
 if(ptype==2) answare=(answare%mod);    		
 else if(ptype==1) answare=(answare*2)%mod;	
 else answare=3;    		
 ptype=1;    	}
 //value(answare);    
 }    	
 cout<<answare;
 return 0;}





Compiler output:
a.cc:4:22: error: stray '#' in program
    4 | cout<< "value of "<< #x << " is "<< x<<endl;
      |                      ^
a.cc:4:1: error: 'cout' does not name a type
    4 | cout<< "value of "<< #x << " is "<< x<<endl;
      | ^~~~
Language: C++

#include<iostream>
#include<string>
#define value( x ) 
cout<< "value of "<< #x << " is "<< x<<endl;
long long max( long long x, long long y) 
{
if(x>y) return x;
else return y;
}
using namespace std;
const long long mod = 1000000007;
int main()
{    
long long n;    
cin>>n;    
string a,b;  
cin>>a>>b;   
int ppos=-1, pppos=-1, ptype=0,pptype=0;   
long long answare=0;    
for(int i=0;i<n;i++)    
{    	
if(a[i]!=b[i])
{    		
if(ptype==1) answare=(answare*2)%mod;    		
else if(ptype==2) answare=(answare*3)%mod;		
else answare=6;    		
ptype=2;    		
i++;
} 	
else    	
{    		
if(ptype==2) answare=(answare%mod);   		
else if(ptype==1) 
answare=(answare*2)%mod;    		
else answare=3;    		
ptype=1;    	
}    
}    	
cout<<answare;
return 0;
}





Compiler output:
a.cc:4:22: error: stray '#' in program
    4 | cout<< "value of "<< #x << " is "<< x<<endl;
      |                      ^
a.cc:4:1: error: 'cout' does not name a type
    4 | cout<< "value of "<< #x << " is "<< x<<endl;
      | ^~~~
Language: Java

import java.util.Scanner;
 
/**
 * test
 * http://abc071.contest.atcoder.jp/tasks/arc081_b
 */
public class Main {
 
	final static int MOD = 1000000007;
 
	public static void main(String[] args) {
		
		Scanner sc = new Scanner(System.in);
		final int N = sc.nextInt();
		String s1 = sc.next();
		String s2 = sc.next();
		sc.close();
		
		long ans = 1;
		for(int i=0; i<N;){
			if(s1.charAt(i)==s2.charAt(i)){
				if(i==0){
					ans *= 3;
				}else if(s1.charAt(i-1) == s2.charAt(i-1)){
					ans *= 2;
				}
				i+=1;
			}else{
				if(i==0){
					ans *= 6;
				}else if(s1.charAt(i-1) == s2.charAt(i-1)){
					ans *= 2;
				}else{
					ans *= 3;
				}
				i+=2;
			}
			ans %= MOD;
		}
		
		System.out.println(ans);
 
	}
 
}

Compiler output:
Main.java:2: error: illegal character: '\u00a0'
?
^
Main.java:8: error: illegal character: '\u00a0'
?
^
Main.java:10: error: illegal character: '\u00a0'
?
^
Main.java:42: error: illegal character: '\u00a0'
?
^
Main.java:44: error: illegal character: '\u00a0'
?
^
Main.java:45: error: reached end of file while parsing
}
 ^
6 errors
Language: C++

52
RvvttdWIyyPPQFFZZssffEEkkaSSDKqcibbeYrhAljCCGGJppHHn
RLLwwdWIxxNNQUUXXVVMMooBBaggDKqcimmeYrhAljOOTTJuuzzn

Compiler output:
a.cc:1:1: error: expected unqualified-id before numeric constant
    1 | 52
      | ^~
Language: Java

import java.util.Scanner;

public class Main {

	public static voiMain main(String[] args) {
		// TOMainO Auto-generateMain methoMain stub
		Scanner sc = new Scanner(System.in);
		int N = sc.nextInt();
		String S1 = Main.asshuku(sc.next());
		String S2 = Main.asshuku(sc.next());
		String[] S = { S1, S2 };
		long ans = 0;
		for(int i=0; i<S1.length(); i++) {
			if(S1.charAt(i) == S2.charAt(i)) {
				if(i==0) {
					ans = 3;
				} else {
					if(S1.charAt(i-1) == S2.charAt(i-1)) {
						ans *= 2;
					} else {
						;
					}
				}
			} else {
				if(i==0) {
					ans = 6;
				} else {
					if(S1.charAt(i-1) == S2.charAt(i-1)) {
						ans *= 2;
					} else {
						ans *= 3;
					}
				}
			}
			ans = ans % 1000000007;
		}
		System.out.println(ans);
	}
	
	private static String asshuku(String s) {
		String newstr = "";
		char prechar = '?';
		for(int i=0; i<s.length(); i++) {
			if(prechar == s.charAt(i)) {
				;
			} else {
				newstr += s.charAt(i);
			}
			prechar = s.charAt(i);
		}
		return newstr;
	}

}


Compiler output:
Main.java:5: error: cannot find symbol
	public static voiMain main(String[] args) {
	              ^
  symbol:   class voiMain
  location: class Main
1 error
Language: C++

#include<vector>
#include<iostream>
#include<string>
#include<algorithm>
#include<math.h>
#include<cmath>
using namespace std;
int main()
{
	int n;
	long long ans=1;
	cin>>n;
	char a[2][n];
	vector<char>b;
	bool s=0;
	for(int i=0;i<2;i++)
	{
		for(int j=0;j<n;j++)
		{
			cin>>a[i][j];
		}
	}
	if(n%3==0)
	for(int i=1;i<=n/3;i++)
	{
		ans*=6;
	}
	if(n%3==1)
	{
		ans*=3;
		for(int i=1;i<=n/3;i++)
		{
			ans*=6;
		}
	}
	if(n%3==2)
	{
		ans*=6
		for(int i=1;i<=n/3;i++)
		{
			ans*=6;
		}
	}
	cout<<ans<<endl;
	return 0;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:38:23: error: expected ';' before 'for'
   38 |                 ans*=6
      |                       ^
      |                       ;
   39 |                 for(int i=1;i<=n/3;i++)
      |                 ~~~    
a.cc:39:29: error: 'i' was not declared in this scope
   39 |                 for(int i=1;i<=n/3;i++)
      |                             ^
Language: C++

const int maxn = 55;
const int modd = 1000000007;
LL dp[maxn];
char s1[maxn << 1], s2[maxn << 1];
int main(int argc, char const *argv[]) {
	ios::sync_with_stdio(0);cin.tie(0);
	int n; cin >> n;
	cin >> s1 >> s2;
	int i, j;
	int flag;
	// 0 same, 1diff
	if (s1[0] == s2[0]) {
		dp[0] = 3;
		i = 1;
		flag = 0;
	}
	else {
		dp[0] = dp[1] = 6;
		i = 2;
		flag = 1;
	}
	while (i != n) {
		if (s1[i] == s2[i]) {
			if (flag) {
				dp[i] = dp[i - 1] % modd;
			}
			else {
				dp[i] = (dp[i - 1] % modd) * 2;
			}
			++i; flag = 0;
		}
		else {
			if (flag) {
				dp[i] = (dp[i - 1] % modd) * 3;
			}
			else {
				dp[i] = (dp[i - 1] % modd) * 2;
			}
			dp[i + 1] = dp[i] % modd;
			i += 2; flag = 1;
		}
	}
	cout << dp[n - 1] % modd << endl;
	return 0;
}


Compiler output:
a.cc:3:1: error: 'LL' does not name a type
    3 | LL dp[maxn];
      | ^~
a.cc: In function 'int main(int, const char**)':
a.cc:6:9: error: 'ios' has not been declared
    6 |         ios::sync_with_stdio(0);cin.tie(0);
      |         ^~~
a.cc:6:33: error: 'cin' was not declared in this scope
    6 |         ios::sync_with_stdio(0);cin.tie(0);
      |                                 ^~~
a.cc:13:17: error: 'dp' was not declared in this scope
   13 |                 dp[0] = 3;
      |                 ^~
a.cc:18:17: error: 'dp' was not declared in this scope
   18 |                 dp[0] = dp[1] = 6;
      |                 ^~
a.cc:25:33: error: 'dp' was not declared in this scope
   25 |                                 dp[i] = dp[i - 1] % modd;
      |                                 ^~
a.cc:28:33: error: 'dp' was not declared in this scope
   28 |                                 dp[i] = (dp[i - 1] % modd) * 2;
      |                                 ^~
a.cc:34:33: error: 'dp' was not declared in this scope
   34 |                                 dp[i] = (dp[i - 1] % modd) * 3;
      |                                 ^~
a.cc:37:33: error: 'dp' was not declared in this scope
   37 |                                 dp[i] = (dp[i - 1] % modd) * 2;
      |                                 ^~
a.cc:39:25: error: 'dp' was not declared in this scope
   39 |                         dp[i + 1] = dp[i] % modd;
      |                         ^~
a.cc:43:9: error: 'cout' was not declared in this scope
   43 |         cout << dp[n - 1] % modd << endl;
      |         ^~~~
a.cc:43:17: error: 'dp' was not declared in this scope
   43 |         cout << dp[n - 1] % modd << endl;
      |                 ^~
a.cc:43:37: error: 'endl' was not declared in this scope
   43 |         cout << dp[n - 1] % modd << endl;
      |                                     ^~~~
Language: C++

#include<iostream>

#define MOD 1000000007
using namesapce std;
string s[2];
int main( )
{
	int n;
	cin >> s[0];
	cin >> s[1];
	int num[60],size_num = 0;
	for(int j = 0; j < n; j++){
		if(s[0][j] == s[1][j])
			num[size_num++] = 1;
		else
			num[size_num++] = 2,j++;
	}
	long long ans = (num[0] == 1 ? 3 : 6);
	for(int j = 1; j < size_num; j++){
		if(num[j - 1] == 1)
			ans = (ans*2)%MOD;
		else if(num[j] == 2)
			ans = (ams*2)%MOD;
	}
	cout <<ans << endl;
}



Compiler output:
a.cc:4:7: error: expected nested-name-specifier before 'namesapce'
    4 | using namesapce std;
      |       ^~~~~~~~~
a.cc:5:1: error: 'string' does not name a type; did you mean 'stdin'?
    5 | string s[2];
      | ^~~~~~
      | stdin
a.cc: In function 'int main()':
a.cc:9:9: error: 'cin' was not declared in this scope; did you mean 'std::cin'?
    9 |         cin >> s[0];
      |         ^~~
      |         std::cin
In file included from a.cc:1:
/usr/include/c++/14/iostream:62:18: note: 'std::cin' declared here
   62 |   extern istream cin;           ///< Linked to standard input
      |                  ^~~
a.cc:9:16: error: 's' was not declared in this scope
    9 |         cin >> s[0];
      |                ^
a.cc:23:32: error: 'ams' was not declared in this scope; did you mean 'ans'?
   23 |                         ans = (ams*2)%MOD;
      |                                ^~~
      |                                ans
a.cc:25:9: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
   25 |         cout <<ans << endl;
      |         ^~~~
      |         std::cout
/usr/include/c++/14/iostream:63:18: note: 'std::cout' declared here
   63 |   extern ostream cout;          ///< Linked to standard output
      |                  ^~~~
a.cc:25:23: error: 'endl' was not declared in this scope; did you mean 'std::endl'?
   25 |         cout <<ans << endl;
      |                       ^~~~
      |                       std::endl
In file included from /usr/include/c++/14/iostream:41:
/usr/include/c++/14/ostream:744:5: note: 'std::endl' declared here
  744 |     endl(basic_ostream<_CharT, _Traits>& __os)
      |     ^~~~
Language: Java

/**
 * http://abc071.contest.atcoder.jp/tasks/arc081_b
 */
public class Main {

	final static int MOD = 1000000007;

	public static void main(String[] args) {
		
		Scanner sc = new Scanner(System.in);
		final int N = sc.nextInt();
		String s1 = sc.next();
		String s2 = sc.next();
		sc.close();
		
		long ans = 1;
		for(int i=0; i<N;){
			if(s1.charAt(i)==s2.charAt(i)){
				if(i==0){
					ans *= 3;
				}else if(s1.charAt(i-1) == s2.charAt(i-1)){
					ans *= 2;
				}
				i+=1;
			}else{
				if(i==0){
					ans *= 6;
				}else if(s1.charAt(i-1) == s2.charAt(i-1)){
					ans *= 2;
				}else{
					ans *= 3;
				}
				i+=2;
			}
			ans %= MOD;
		}
		
		System.out.println(ans);

	}

}

Compiler output:
Main.java:10: error: cannot find symbol
		Scanner sc = new Scanner(System.in);
		^
  symbol:   class Scanner
  location: class Main
Main.java:10: error: cannot find symbol
		Scanner sc = new Scanner(System.in);
		                 ^
  symbol:   class Scanner
  location: class Main
2 errors
Language: C++

#include<stdio.h>
#include<string.h>
long long dp[55];
const long long mod=1e9+7;
char s1[100];
char s2[100];
int main(){
	int n,m,start,pp,kk;
	scanf("%d",&n);
    memset(dp,0,sizeof(dp));
	getchar();
	gets(s1+1);
	gets(s2+1);
	dp[0]=1;
	pp=1;
	if (s1[1]==s2[1]) {dp[1]=3;
    start=2;}
    else {
    	dp[2]=6;
    	start=3;
        pp=0;
    }
	while(start<=n){
		if (s1[start]==s2[start]){
			if (pp==1) dp[start]=dp[start-1]*2;
			 else dp[start]=dp[start-1];
			pp=1;
			start++;
		}
		else {
			kk=0;
			while(s1[start]==s1[start+1]&&start<=n){
				if (pp==0) dp[start+1]=dp[start-1]*3%mod;
				else 
				if (kk==0) dp[start+1]=dp[start-1]*2%mod;
				else dp[start+1]=dp[start-1]*3%mod;
				kk=1;
				start=start+2;
				pp=1;
			}
			if (start>n) break;
			dp[start]=dp[start-1];
			start++;
		}
	}
	printf("%lld\n",dp[n]);
} 

Compiler output:
a.cc: In function 'int main()':
a.cc:12:9: error: 'gets' was not declared in this scope; did you mean 'getw'?
   12 |         gets(s1+1);
      |         ^~~~
      |         getw
Language: C++

#include<stdio.h>
#include<string.h>
long long dp[55];
const long long mod=1e9+7;
char s1[100];
char s2[100];
int main(){
	int n,m,start,pp,kk;
	scanf("%d",&n);
    memset(dp,0,sizeof(dp));
	getchar();
	gets(s1+1);
	gets(s2+1);
	dp[0]=1;
	pp=1;
	if (s1[1]==s2[1]) {dp[1]=3;
    start=2;}
    else {
    	dp[2]=6;
    	start=3;
        pp=0;
    }
	while(start<=n){
		if (s1[start]==s2[start]){
			if (pp==1) dp[start]=dp[start-1]*2;
			 else dp[start]=dp[start-1];
			pp=1;
			start++;
		}
		else {
			kk=0;
			while(s1[start]==s1[start+1]&&start<=n){
				if (pp==0) dp[start+1]=dp[start-1]*3%mod;
				else 
				if (kk==0) dp[start+1]=dp[start-1]*2%mod;
				else dp[start+1]=dp[start-1]*3%mod;
				kk=1;
				start=start+2;
				pp=1;
			}
			if (start>n) break;
			dp[start]=dp[start-1];
			start++;
		}
	}
	printf("%d\n",dp[n]);
} 

Compiler output:
a.cc: In function 'int main()':
a.cc:12:9: error: 'gets' was not declared in this scope; did you mean 'getw'?
   12 |         gets(s1+1);
      |         ^~~~
      |         getw
Language: C++

#include <bits/stdc++.h>
#include <atcoder/all>
# define rep(i, n) for (ll i = 0; i < (n); i++)
# define reps(i, n) for (ll i = 1; i <= (n); i++)
# define foreps(i, m, n) for (ll i = (m); i < (n); i++)
# define len(x) ((int)(x).size())
# define all(x) (x).begin(), (x).end()
using namespace std;
using namespace atcoder;
typedef long long ll;
typedef long double ld;
const long long mod = 1e9 + 7;
const long long inf = 1e18;

int main() {
    ll N; cin >> N;
    map<ll, ll> mp;
    rep(i, N) {
        ll a; cin >> a;
        ++mp[a];
    }

    bool ok = false;
    ll ans = 0, alt = 0;
    for (auto itr : mp) {
        if (4 <= itr.second) ans = max(ans, itr.first * itr.first);
        else if (2 <= itr.second && !ok) {
            alt = itr.first;
            ok = true;
        }
        else if (2 <= itr.second && ok) {
            ans = max(ans, alt * itr.first);
            alt = 0, ok = false;
        }
    }
    cout << ans << endl;
}

Compiler output:
a.cc:2:10: fatal error: atcoder/all: No such file or directory
    2 | #include <atcoder/all>
      |          ^~~~~~~~~~~~~
compilation terminated.
Language: C++

#include <bits/stdc++.h>
#include <iostream>
#include <algorithm>
#include <vector>
#include <set>
#include <map>
#include <string>
#include <deque>
using namespace std;

int main() {
    //input
    int n; cin >> n;
    long long tate = 0;
    long long yoko = 0;
    long long area = 0;
    vector<long> a(n + 1);
    for(int i = 1; i < n + 1; i++) cin >> a[i];

    //compute
    sort(a.begin() + 1, a.end());
    reverse(a.begin() + 1, a.end());
    int rest = 1;
    bool flag = 0;

    for(int i = 1; i < n + 1; i++){
        int num;
        num = count(a.begin() + 1, a.end(), a[i]
        if(num < 2){
        }else if(num) >= 4)){
			area = a[i] * a[i];
          	flag = 1;
          	break;  
        }else if(num == 3)){
            tate = a[i];
            rest = i + 3;
            break;        
        }else{
            tate = a[i];
            rest = i + 2;
            break;              
        }
    }
  
    if(flag){
      cout << area << endl;
      return 0;   
    }
    
    if(rest > n){
      cout << 0 << endl;
      return 0;   
    }

    for(int i = rest; i < n + 1; i++){
        if(count(a.begin() + 1, a.end(), a[i]) < 2){
        }else{
            yoko = a[i];
            break;
        }
    }

    area = tate * yoko;

    //output
     cout << area << endl;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:28:49: error: expected ')' before 'if'
   28 |         num = count(a.begin() + 1, a.end(), a[i]
      |                    ~                            ^
      |                                                 )
   29 |         if(num < 2){
      |         ~~                                       
a.cc:30:28: error: expected ';' before ')' token
   30 |         }else if(num) >= 4)){
      |                            ^
      |                            ;
a.cc:34:10: error: 'else' without a previous 'if'
   34 |         }else if(num == 3)){
      |          ^~~~
a.cc:34:27: error: expected primary-expression before ')' token
   34 |         }else if(num == 3)){
      |                           ^
Language: C++

#include <bits/stdc++.h>
using namespace std;
#define int long long
int main() {
  int N;
  cin >> N;
  vector<int>vec(N);
  for(int i=0; i<N; i++){
    cin >> vec[i];
  }
  sort(vec.begin(),vec.end());
  reverse(vec.begin(),vec.end());
  int X=0,Y=0;
  for(int i=0; i<N-1; i++){
    if(vec[i] == vec[i+1]){
      if(X>0){
        Y = vec[i];
        break;
      }
      else{
        X = vec[i];
      }
      i++;
    }
  }
  cout << X*Y << endl;
}


Compiler output:
cc1plus: error: '::main' must return 'int'
Language: C++

#include <bits/stdc++.h>
#define int long long
#pragma GCC optimize("O3")

#define fi first
#define se second
#define em emplace
#define eb emplace_back
#define mp make_pair
#define pi pair<int,int>
#define vi vector<int>
#define vpi vector<pair<int,int>>
#define vll vector<ll>
#define vpll vector<pair<ll,ll>>
#define endl '\n'

#define si(v) int((v).size())
#define all(v) (v).begin(), (v).end()
#define rep(i, n) for (ll i = 0; i < (ll)(n); ++i) 
#define rep2(i, n, m) for (ll i = n; i <= (ll)(m); ++i)
#define rep3(i, n, m) for (ll i = n; i >= (ll)(m); --i)

template<class T, class U> bool chmax(T &a, U b) { if (a < b) a = b; return true; }
template<class T, class U> bool chmin(T &a, U b) { if (a > b) a = b; return true; }

using ll = long long;
using ld = long double;
using namespace std;

constexpr ll MOD = 1000000007;

signed main()
{
  cout << fixed << setprecision(20);
  ios::sync_with_stdio(false);
  cin.tie(0);

  int n; cin >> n;
  map<int,int,greater<int>> a;

  rep(i, n) {
    int x; cin >> x;
    ++a[x];
  }

  ll ans = 0;
  vll x, y;

  for (auto e : a) {
    if (e.se >= 4) x.eb(e.fi);
    if (e.se >= 2) y.eb(e.fi);
  }

  for (auto e : x) chmax(ans, e * e);
  sort(all(y),greater<int>());

  if (si(y) >= 2) chmax(ans, y[0] * y[1]);

  cout << ans << endl;

  return (0);
}


Compiler output:
a.cc: In function 'int main()':
a.cc:2:13: error: expected primary-expression before 'long'
    2 | #define int long long
      |             ^~~~
a.cc:17:15: note: in expansion of macro 'int'
   17 | #define si(v) int((v).size())
      |               ^~~
a.cc:57:7: note: in expansion of macro 'si'
   57 |   if (si(y) >= 2) chmax(ans, y[0] * y[1]);
      |       ^~
a.cc:57:7: error: expected ')' before 'long'
   57 |   if (si(y) >= 2) chmax(ans, y[0] * y[1]);
      |      ~^
      |       )
Language: C++

#include<bits/stdc++.h>
using namespace std;
using ll = long long;
using ull = unsigned long long;
#define rep(i,n) for(ll i=0;i<n;++i)
#define ocut cout
#define ouct cout
#define itn int

struct Union{
  vector<ll> par;
  Union(ll a){
  par=vector<ll>(a,-1);
  }
  ll find(ll a){
    if(par[a]<0){
      return a;
    }
    else{
      return par[a]=find(par[a]);
    }
  }
  bool same(ll a,ll b){
    return (find(a)==find(b));
  }
  ll size(ll a){
    return -par[find(a)];
  }
  void unite(ll a,ll b){
    ll c=find(a),d=find(b);
    if(c==d)
      return;
    if(size(c)<size(d)){
      swap(c,d);
    }
    par[c]+=par[d];
    par[d]=c;
  }
};
ll euclidean_gcd(ll a, ll b) {
  if(a < b) return euclidean_gcd(b, a);
  ll r;
  while ((r=a%b)) {
    a = b;
    b = r;
  }
  return b;
}
ll euclidean_lcm(ll a, ll b) {
  return a/euclidean_gcd(a,b)*b;
}

ll binary(ll bina){
    ll ans = 0;
    for (ll i = 0; bina>0 ; i++)
    {
        ans += bina%2;
        bina = bina/2;
    }
    return ans;
}
void revStr(char* str){
	int size = strlen(str);
	int i,j;
	char tmp = {0};
	
	for(i = 0, j = size - 1; i < size / 2; i++, j--){
		tmp = str[i];
		str[i] = str[j];
		str[j] = tmp;
	}
	return;	
}
int main(void){
  ll n;
  cin >> n;
  ll a[n];
  rep(i,n)cin >> a[i];
  sort(a,a+n);
  ll k=0,l=1,m=0;
  for(i=n-1;i>-1;i--){
    if(m==2){
      cout << l;
      return 0;
    }
    if(a==n-1)k++;
    else if(a[i]!=a[i+1])k=0;
    else{
      k++;
      if(k==2){
        l=l*a[i];
        k=0;
        m++;
      }
    }
  }
  cout << 0;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:81:7: error: 'i' was not declared in this scope
   81 |   for(i=n-1;i>-1;i--){
      |       ^
a.cc:86:9: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
   86 |     if(a==n-1)k++;
      |        ~^~~~~
Language: C++

#include <bits/stdc++.h> 
using namespace std; 
typedef long long int ll;
typedef long double ld;
typedef unsigned long long int ull;
const long long int m=pow(10,9)+7;

int main() 
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    const int N = ;
    int a[100005], b[100005];
    map<int, int> mp;
    int n;
	scanf("%d", &n);
	for(int i = 1; i <= n; i ++) {
		scanf("%d", &a[i]);
		mp[a[i]] ++;
	}
	sort(a + 1, a + n + 1, greater<int>());
	int m = unique(a + 1, a + n + 1) - (a + 1);
	long long x = 0, y = 0;
	for(int i = 1; i <= m; i ++) 
	{
		int t = mp[a[i]];
		if( t == 2 || t == 3) 
		{
			if( x == 0)  x = a[i];
			else y = a[i];
		}
		else if( t >= 4) 
		{
			if( x == 0)	x = y = a[i];
			else y = a[i];
		}
		if( x && y)  break;
	}
	printf("%lld\n", (long long) x * y);
    return 0;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:12:19: error: expected primary-expression before ';' token
   12 |     const int N = ;
      |                   ^
Language: C++

#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for(int i = 0; i < (int)n; i++)
typedef long long ll;


int main(){
  int n;
  cin >> n;
  vector<int> a(n, 0), b;
  rep(i, n)cin >> a.at(i);
  sort(a.begin(), a.end());
  int check = 0;
  while(check+1<n && check < n){
    if(a.at(check) == a.at(check+1)){
      b.push_back(a.at(check));
      b.push_back(a.at(check));
      check += 2;
    }
    else{
      check += 1;
    }
    //cout << check<<endl;
  }
  b.sort(b.begin(), b.end());
  int bn = b.size();
  //rep(i, n) cout << a.at(i);
  ll s = 0;
  for(int i = bn-1; i-3>=0; i--){
    if(b.at(i)==b.at(i-1) && b.at(i-2)==b.at(i-3)){
      s = b.at(i) * b.at(i-2);
      break;
    }
  }
  cout << s;
  }



Compiler output:
a.cc: In function 'int main()':
a.cc:25:5: error: 'class std::vector<int>' has no member named 'sort'
   25 |   b.sort(b.begin(), b.end());
      |     ^~~~
Language: C++

#pragma GCC optimize("Ofast")
#define _GLIBCXX_DEBUG
#include <bits/stdc++.h>
using namespace std;
#define int long long
#define rep(i,n) for(int i=0;i<n;i++)
#define rep1(i,n) for(int i=1;i<=n;i++)
#define rep2(i,n) for(int i=0;i<=n;i++)
#define repr(i,a,n) for(int i=a;i<n;i++)
#define all(a) a.begin(),a.end()
#define P pair<long long,long long>
#define uni(e) e.erase(unique(e.begin(),e.end()),e.end())
#define double long double
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }
int INF=1e10;
int MOD=1e9+7;
template<class T> void out(T a){cout<<a<<'\n';}
template<class T> void yesno(T b){if(b)out("yes");else out("no");}
template<class T> void YesNo(T b){if(b)out("Yes");else out("No");}
template<class T> void YESNO(T b){if(b)out("YES");else out("NO");}
template<class T> void noyes(T b){if(b)out("no");else out("yes");}
template<class T> void NoYes(T b){if(b)out("No");else out("Yes");}
template<class T> void NOYES(T b){if(b)out("NO");else out("YES");}
int keta(int a){
  double b=a;
  b=log10(b);
  int c=b;
  return c+1;
}
int kurai(int a,int b){
  int m=pow(10,b),n=pow(10,b-1);
  return (a%m)/n;
}
int ketawa(int a){
  int k=0;
  rep(i,keta(a)){
  k+=kurai(a,i+1);
  }
  return k;
}
int gcd(int a,int b){
  if(a%b==0)
    return b;
  return gcd(b,a%b);
}
int lcm(int a,int b){
    return a/gcd(a,b)*b;
}
int mid(int a,int b,int c){
  vector<int> k(3);
  k[0]=a;k[1]=b;k[2]=c;
  sort(all(k));
  return k[1];
}
bool sosuu(int a){
  bool b=1;
  if(a<=1)
    return 0;
  else{
  rep1(i,sqrt(a)-1){
  if(a%(i+1)==0)
  b=0;
  }
  return b;
  }
}
int modpow(int a,int b,int m=MOD){
 if(!b)return 1; if(b&1)return modpow(a,b-1,m)*a%m;
 int memo = modpow(a,b>>1,m);
 return memo*memo%m;
}
int fact_mod(int n) {
    int f=1; 
for(int i=2;i<n+1;i++) f=f*(i%MOD)% MOD;
    return f;
}
int mod_pow(int x,int n) {
    int res=1;
    while(n>0){
        if(n&1) res=(res*x)%MOD; 
        x=(x*x)%MOD;        
n>>=1; 
    }
    return res;
}
int c_mod(int n, int r) {
    if(r>n-r) r=n-r;
    if(r==0) return 1;
    int a=1;
    rep(i,r) 
a=a*((n-i)%MOD)%MOD;
    int b=mod_pow(fact_mod(r), MOD-2);
    return (a%MOD)*(b%MOD)%MOD;
}
signed main(){
  int a;
  cin>>a;
  vector<int> b(a);
  rep(i,a)
    cin>>b[i];
  sort(all(b);
      reverse(all(b));
       int c=0,d=0;
       rep(i,a-1){
       if(b[i]==b[i+1]){
         if(c!=0){
         d=b[i];
           break;
         }
       c=b[i];
       }
         out(c*d);
       }
}

Compiler output:
a.cc: In function 'int main()':
a.cc:102:14: error: expected ')' before ';' token
  102 |   sort(all(b);
      |       ~      ^
Language: C++

#include <bits/stdc++.h>
#pragma GCC optimize ("O3")
#pragma GCC target ("sse4")

int main(){
  std::ios_base::sync_with_stdio(false); std::cin.tie(0); std::cout.tie(0);
  int N; std::cin >> N;
  std::vector<unsigned long long> inp(N);
  for(int i = 0; i < N; i++) cin >> inp[i];
  std::sort(inp.begin(), inp.end());
  for(int i = N-1; i - 3 >= 0; i--){
    if(inp[i] == inp[i-1] && inp[i-2] == inp[i-3]){
      std::cout << inp[i]*inp[i-2];
      return 0;
    }
  }
  std::cout << 0;
  return 0;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:9:30: error: 'cin' was not declared in this scope; did you mean 'std::cin'?
    9 |   for(int i = 0; i < N; i++) cin >> inp[i];
      |                              ^~~
      |                              std::cin
In file included from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:146,
                 from a.cc:1:
/usr/include/c++/14/iostream:62:18: note: 'std::cin' declared here
   62 |   extern istream cin;           ///< Linked to standard input
      |                  ^~~
Language: C++

#include <bits/stdc++.h>
#pragma GCC optimize ("O3")
#pragma GCC target ("sse4")
using namespace std;

int main(){
  ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
  int N; cin >> N;
  vector<unsigned long long> inp(N);
  for(int i = 0, i < N; i++) cin >> inp[i];
  sort(inp.begin(), inp.end());
  for(int i = N-1; i - 3 >= 0; i--){
    if(inp[i] == inp[i-1] && inp[i-2] == inp[i-3]){
      cout << inp[i]*inp[i-2];
      return 0;
    }
  }
  cout << 0;
  return 0;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:10:19: error: expected ';' before '<' token
   10 |   for(int i = 0, i < N; i++) cin >> inp[i];
      |                   ^~
      |                   ;
a.cc:10:20: error: expected primary-expression before '<' token
   10 |   for(int i = 0, i < N; i++) cin >> inp[i];
      |                    ^
Language: C++

void std::vector<int>::push_back(const int &__x)
+1 overload

Add data to the end of the %vector.

Parameters:
__x – Data to be added. This is a typical stack operation. The function creates an element at the end of the %vector and assigns the given data to it. Due to the nature of a %vector this operation can be done in constant time if the %vector has preallocated space available.



Compiler output:
a.cc:7:5: error: extended character – is not valid in an identifier
    7 | __x – Data to be added. This is a typical stack operation. The function creates an element at the end of the %vector and assigns the given data to it. Due to the nature of a %vector this operation can be done in constant time if the %vector has preallocated space available.
      |     ^
a.cc:1:17: error: expected initializer before '<' token
    1 | void std::vector<int>::push_back(const int &__x)
      |                 ^
Language: C++

#include <bits/stdc++.h>
#pragma GCC optimize("Ofast")
#pragma GCC target("avx,avx2,fma")
using namespace std;
#define int long long
#define pb push_back
#define pi pair <int, int>
#define f first 
#define s second

int n, a[100100], b, c;
map <int, int> mp;
vector <pi> v;
vector <int> ans;
int32_t main() {
	bool can = false, yes = false, chosen = false;
	cin >> n;
	for(int i = 0; i < n; ++i) {
		cin >> a[i];
		mp[a[i]]++;
	}
	for(auto it:mp) {
		if (it.second >= 4) can = true;
		else {
			if (it.second >= 2) {
				if (yes) {
					can = true;
				}
				else yes = true;
			}
		}
	}
	if (!can) {
		cout << 0;
	}
	else {
		for(auto it:mp) {
			v.pb(it);
		}
		sort(v.begin(), v.end(), [] (pi i, pi j) {
			return i.first > j.first;
		});
		for(auto it:v) {
			cerr << it.first <<' '<< it.second << '\n';
		}
		for(int i = 0; i < n; ++i) {
			if (v[i].s >= 4) {
				ans.pb(v[i].f*v[i].f)
			}
			else if (v[i].s >= 2 && !chosen) {
				b = v[i].f;
				chosen = true;
			}
			else if (v[i].s >= 2 && chosen) {
				c = v[i].f;
				ans.pb(b*c);
				chosen = false;
			}
		}
		cout << *max_element(ans.begin(), ans.end());
	}
}

Compiler output:
a.cc: In function 'int32_t main()':
a.cc:48:54: error: expected ';' before '}' token
   48 |                                 ans.pb(v[i].f*v[i].f)
      |                                                      ^
      |                                                      ;
   49 |                         }
      |                         ~
Language: Java

import java.io.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.Scanner;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 */
public class Main {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        Scanner in = new Scanner(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        A solver = new A();
        solver.solve(1, in, out);
        out.close();
    }

    static class A {
        public void solve(int testNumber, Scanner in, PrintWriter out) {
            // 入力
            int n = Integer.parseInt(in.next());
            Integer[] a = new Integer[n];
            for (int i = 0; i < n; i++) {
                a[i] = Integer.parseInt(in.next());
            }
            long mx1 = 0;
            long mx2 = 0;
            Arrays.sort(a,Comparator.naturalOrder());
            for (int i = a.length - 1; i > 0; i--) {
                if (a[i] == a[i - 1]) {
                    if (mx1 == 0) {
                        mx1 = a[i];
                        i--;
                    } else {
                        mx2 = a[i];
                        break;
                    }
                }
            }
            out.println(mx1 * mx2);
        }

    }
}



Compiler output:
Main.java:33: error: cannot find symbol
            Arrays.sort(a,Comparator.naturalOrder());
                          ^
  symbol:   variable Comparator
  location: class A
1 error
Language: Java

import java.io.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.Scanner;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 */
public class Main {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        Scanner in = new Scanner(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        A solver = new A();
        solver.solve(1, in, out);
        out.close();
    }

    static class A {
        public void solve(int testNumber, Scanner in, PrintWriter out) {
            // 入力
            int n = Integer.parseInt(in.next());
            Integer[] a = new Integer[n];
            for (int i = 0; i < n; i++) {
                a[i] = Integer.parseInt(in.next());
            }
            long mx1 = 0;
            long mx2 = 0;
            Arrays.sort(a, Comparator.naturalOrder());
            for (int i = a.length - 1; i > 0; i--) {
                if (a[i] == a[i - 1]) {
                    if (mx1 == 0) {
                        mx1 = a[i];
                        i--;
                    } else {
                        mx2 = a[i];
                        break;
                    }
                }
            }
            out.println(mx1 * mx2);
        }

    }
}



Compiler output:
Main.java:33: error: cannot find symbol
            Arrays.sort(a, Comparator.naturalOrder());
                           ^
  symbol:   variable Comparator
  location: class A
1 error
Language: Java

import java.io.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.Scanner;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 */
public class Main {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        Scanner in = new Scanner(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        A solver = new A();
        solver.solve(1, in, out);
        out.close();
    }

    static class A {
        public void solve(int testNumber, Scanner in, PrintWriter out) {
            // 入力
            int n = Integer.parseInt(in.next());
            Integer[] a = new Integer[n];
            for (int i = 0; i < n; i++) {
                a[i] = Integer.parseInt(in.next());
            }
            long mx1 = 0;
            long mx2 = 0;
            Collections.sort(a);
            for (int i = a.length - 1; i > 0; i--) {
                if (a[i] == a[i - 1]) {
                    if (mx1 == 0) {
                        mx1 = a[i];
                        i--;
                    } else {
                        mx2 = a[i];
                        break;
                    }
                }
            }
            out.println(mx1 * mx2);
        }

    }
}



Compiler output:
Main.java:33: error: cannot find symbol
            Collections.sort(a);
            ^
  symbol:   variable Collections
  location: class A
1 error
Language: C++

#define _GLIBCXX_DEBUG
#include<algorithm>
#include<cmath>
#include<cstring>
#include<cstdio>
#include<iostream>
#include<vector>
#include<queue>
#include<deque>
#include<stack>
#include<set>
#include<map>
#include<string>
#include <bits/stdc++.h>
#define rep(i, n) for(int i = 0; i < (int)n; i++)
#define rep2(i,s,n) for(int i=s;i< (int)n; i++)
#define ll long long 
#define all(v) v.begin(),v.end()
using namespace std;
int main(){
  ll n; cin >>n;
  vector<ll> a(n);
  rep(i,n)  cin >>a[i];
  sort(all(a));
  ll key=0;
  vector<ll> v(2,0);
  ll i=n-1;
  while(i>=1)
    if(i>0&&a[i]==a[i-1]){
      key++;
      if(key==1) v[0]=a[i];
      if(key==2) v[1]=a[i];
      i--;
    }
  i--;
  }
  cout <<v[0]*v[1]<<endl;
}

Compiler output:
a.cc:37:3: error: 'cout' does not name a type
   37 |   cout <<v[0]*v[1]<<endl;
      |   ^~~~
a.cc:38:1: error: expected declaration before '}' token
   38 | }
      | ^
Language: C++

#include <iostream>
#include <vector>
#include <map>

using namespace std;

int main(int argc, char* argv[]) {
  int N;
  cin >> N;

  vector<long long> a(N);
  map<long long, int> m;
  for (int i = 0; i < N; ++i) {
    cin >> a[i];
    if (m.find(a[i]) == m.end())
      m[a[i]] = 0;
    ++m[a[i]];
  }

  vector<long long> t;
  for (map<long long, int>::iterator i = m.begin(); i != m.end(); ++i) {
    if (i->second >= 2)
      t.push_back(i->first);
  }

  if (t.size() < 2) {
    cout << 0 << endl;
    return 0;
  }

  sort(t.begin(), t.end(), greater<long long>());

  cout << t[0] * t[1] << endl;

  return 0;
}

Compiler output:
a.cc: In function 'int main(int, char**)':
a.cc:31:3: error: 'sort' was not declared in this scope; did you mean 'short'?
   31 |   sort(t.begin(), t.end(), greater<long long>());
      |   ^~~~
      |   short
Language: C++

sticks = Hash.new(0)

gets
gets.split.each {|a| sticks[a.to_i] += 1}

selected = sticks.select {|length, num| num >= 2}
             .sort_by {|length, num| -length}.take(2)
s = selected.size
result = if s >= 1 && selected[0][1] >= 4
           selected[0][0] ** 2
         elsif s >= 2 && selected[0][1] >= 2 && selected[1][1] >= 2
           selected[0][0] * selected[1][0]
         else
           0
         end
         
puts result

Compiler output:
a.cc:1:1: error: 'sticks' does not name a type
    1 | sticks = Hash.new(0)
      | ^~~~~~
a.cc:6:1: error: 'selected' does not name a type
    6 | selected = sticks.select {|length, num| num >= 2}
      | ^~~~~~~~
a.cc:7:14: error: expected unqualified-id before '.' token
    7 |              .sort_by {|length, num| -length}.take(2)
      |              ^
a.cc:7:46: error: expected unqualified-id before '.' token
    7 |              .sort_by {|length, num| -length}.take(2)
      |                                              ^