criyle/codenet-compile-errors huggingface dataset:
Language: C++

#include <iostream>
#include <vector>

using namespace std;
template<class T> inline bool chmax(T &a, T b){ if(a < b){a = b; return true;} return false;}

struct Edge{
    int from,to,weight;
    Edge(int f,int t,int w) : from(f), to(t), weight(w){}
};

using Edges = vector<Edge>;
using Graph = vector<Edges>;

class Tree{
    public:
        Tree(int size) : mGraph(size), mMemo(size) {}
        void add_edge(int s, int t, int w = 1){
            mGraph[s].emplace_back(s,t,w);
            mGraph[t].emplace_back(t,s,w);
        }

        // diameter of a tree
        pair<int,int> dfs(int v, int pv){
            pair<int,int> ret(0,v);
            for(Edge nv : mGraph[v]){
                if(nv.to == pv) continue;
                pair<int,int> tmp = dfs(nv.to,v);
                if(chmax(ret.first,tmp.first + nv.weight)){
                    ret.second = tmp.second;
                }
            }
            return ret;
        }

        int diameter(){
            pair<int,int> s = dfs(0,-1);
            pair<int,int> t = dfs(s.second,-1);
            return t.first;
        }
        //
    private:
        Graph mGraph;
};

int main(){
    int n,s,t,w;
    cin >> n;
    Tree tree(n);
    for(int i = 0; i < n-1; ++i){
        cin >> s >> t;
        --s;--t;
        tree.add_edge(s,t);
    }
    cout << (tree.diameter() % 3 != 1 ? "First" : "Second") << '\n';
    return 0;
}

Compiler output:
a.cc: In constructor 'Tree::Tree(int)':
a.cc:17:40: error: class 'Tree' does not have any field named 'mMemo'
   17 |         Tree(int size) : mGraph(size), mMemo(size) {}
      |                                        ^~~~~
Language: C++

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

const int maxV = 111111;
int N;
vector<int> G[maxV]; // 頂点情報のみのグラフ

// treeDFS(親, 現在地, 根から現在地までの距離, 根からの最大の距離, 根から最大の距離となる頂点
void treeDFS(int from, int current, int dist, int &maxDist, int &maxVertex) {
    // 距離と終点を更新
    if (dist > maxDist) {
        maxDist = dist;
        maxVertex = current;
    }

    for (auto to : G[current]) {
        // 逆流を防ぐ
        if (to == from) continue;
        treeDFS(current, to, dist + 1, maxDist, maxVertex);
    }
}

int getTreeDiameter() {
    int start = 0, end = 0, maxDist = 0;
    treeDFS(-1, start, 0, maxDist, end);
    start = end, end = 0, maxDist = 0;
    treeDFS(-1, start, 0, maxDist, end);
		//cout << start + 1 << " " << end + 1 << endl;
return maxDist;
}

int main() {
	cin >> N;
	for (int i = 0; i < N-1; i++) {
		int a, b;
		cin >> a >> b;
		a--, b--;
		G[a].push_back(b);
		G[b].push_back(a);
	}

	a=getTreeDiameter();
  a++;
  
    
  puts(a%2==0?"Second":"First");

	return 0;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:42:9: error: 'a' was not declared in this scope
   42 |         a=getTreeDiameter();
      |         ^
Language: Java

package nishiki_quest;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;

public class AtCoder {

	public static void main(String[] args) throws NumberFormatException, IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		int N = Integer.parseInt(br.readLine());

		String[] input;
		ArrayList<Point> points = new ArrayList<Point>();

		input = br.readLine().split(" ");
		points.add(new Point(Integer.parseInt(input[0])));
		points.add(new Point(Integer.parseInt(input[1])));
		points.get(0).connect(points.get(1));
		points.get(1).connect(points.get(0));
		//sideにindex0を追加するコードがここ
		//以下forで辺情報を読み込み、Pointに格納
		for(int i=1;i<N;i++) {
			input = br.readLine().split(" ");
			int[] side = {Integer.parseInt(input[0]),Integer.parseInt(input[1])};
			for(int j=1;j<=i;j++) {
				Point target = points.get(j);
				if(side[0]==target.no) {
					Point newPoint = new Point(side[1]);
					points.add(newPoint);
					target.connect(newPoint);
					newPoint.connect(target);
					break;
				}else if(side[1]==target.no) {
					Point newPoint = new Point(side[0]);
					points.add(newPoint);
					target.connect(newPoint);
					newPoint.connect(target);
					break;
				}
			}
		}

		PointsMng tree = new PointsMng(points);

		if(tree.calcFar()%3==2)
			System.out.println("Second");
		else
			System.out.println("First");

	}

}

class Point{
	int no;
	int lengthToFar;
	ArrayList<Point> next;

	Point(int no){
		this.no = no;
	}

	void connect(Point next) {
		this.next.add(next);
	}

	int calcMaxLength(Point back){
		int max =0;
		for(Point nextPoint:next) {
			if(nextPoint != back) {
				int length = nextPoint.calcMaxLength(this)+1;
				if(max < length) max=length;
			}
		}
		return max;
	}
}

class PointsMng{

	ArrayList<Point> tree;
	ArrayList<Point> ends;
	PointsMng(ArrayList<Point> tree){
		this.tree = tree;
		for(Point point:tree) {
			if(point.next.size()==1) ends.add(point);
		}
	}

	int calcFar(){
		int max = 0;
		for(Point end:ends) {
			if(max < (end.lengthToFar = end.calcMaxLength(null))) {
				max = end.lengthToFar;
			}
		}
		return max;
	}
}


Compiler output:
Main.java:8: error: class AtCoder is public, should be declared in a file named AtCoder.java
public class AtCoder {
       ^
1 error
Language: Java


import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;

public class AtCoder {

	public static void main(String[] args) throws NumberFormatException, IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		int N = Integer.parseInt(br.readLine());

		String[] input;
		ArrayList<Point> points = new ArrayList<Point>();

		input = br.readLine().split(" ");
		points.add(new Point(Integer.parseInt(input[0])));
		points.add(new Point(Integer.parseInt(input[1])));
		points.get(0).connect(points.get(1));
		points.get(1).connect(points.get(0));
		//sideにindex0を追加するコードがここ
		//以下forで辺情報を読み込み、Pointに格納
		for(int i=1;i<N;i++) {
			input = br.readLine().split(" ");
			int[] side = {Integer.parseInt(input[0]),Integer.parseInt(input[1])};
			for(int j=1;j<=i;j++) {
				Point target = points.get(j);
				if(side[0]==target.no) {
					Point newPoint = new Point(side[1]);
					points.add(newPoint);
					target.connect(newPoint);
					newPoint.connect(target);
					break;
				}else if(side[1]==target.no) {
					Point newPoint = new Point(side[0]);
					points.add(newPoint);
					target.connect(newPoint);
					newPoint.connect(target);
					break;
				}
			}
		}
		
		PointsMng tree = new PointsMng(points);

		if(tree.calcFar()%3==2) 
			System.out.println("Second");
		else
			System.out.println("First");

	}

}

class Point{
	int no;
	int lengthToFar;
	ArrayList<Point> next;

	Point(int no){
		this.no = no;
	}
	
	void connect(Point next) {
		this.next.add(next);
	}
	
	int calcMaxLength(Point back){
		int max =0;
		for(Point nextPoint:next) {
			if(nextPoint != back) {
				int length = nextPoint.calcMaxLength(this)+1;
				if(max < length) max=length;
			}
		}
		return max;
	}
}

class PointsMng{
	
	ArrayList<Point> tree;
	ArrayList<Point> ends;
	PointsMng(ArrayList<Point> tree){
		this.tree = tree;
		for(Point point:tree) {
			if(point.next.size()==1) ends.add(point);
		}
	}
	
	int calcFar(){
		int max = 0;
		for(Point end:ends) {
			if(max < (end.lengthToFar = end.calcMaxLength(null))) {
				max = end.lengthToFar;
			}
		}
		return max;
	}
}

Compiler output:
Main.java:7: error: class AtCoder is public, should be declared in a file named AtCoder.java
public class AtCoder {
       ^
1 error
Language: C++

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

int head[200010],o=0,di=-1,ans=0,n;
bool vis[200010];
struct edge{
	int to,link;
}e[400010];

void add_edge(int u,int v){
	e[++o].link=head[u],e[o].to=v,head[u]=o;
	e[++o].link=head[v],e[o].to=u,head[v]=o;
}
void dfs(int u,int d,bool k){
	vis[u]=k;
	if(ans<d){
		ans=d;
		di=u;
	}
	for(int i=head[u];i;i=e[i].link){
		if(vis[e[i].to]!=k) dfs(e[i].to,d+1,k);
	}
}

int main(){
	scanf("%d",&n);
	for(int i=1,u,v;i<n;i++)
      scanf("%d %d",&u,&v),add_edge(u,v);
	dfs(1,1,1);
	dfs(di,1,0);
	if(ans%3==2)
      printf("Second\n")
    else
      printf("First\n");
	return 0;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:32:25: error: expected ';' before 'else'
   32 |       printf("Second\n")
      |                         ^
      |                         ;
   33 |     else
      |     ~~~~
Language: C++

#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <algorithm>
#include <queue>
 
namespace IO{
    const int insiz = 1 << 12, outsiz = 1 << 18;
    char in[insiz], *A(in), *B(in); char out[outsiz], *ptr(out);
    inline char getc(){
    	#ifndef LOCAL
        return (A == B) && (B = (A = in) + fread(in, 1, insiz, stdin), A == B) ? EOF : *A++;
        #endif
        return getchar();
    }
    template <typename T> inline T read(){
        T ret(0), p(1); char ch(getc());
        while(ch < '0' || ch > '9'){
            if(ch == '-') p = -1; ch = getc();
        }
        while(ch >= '0' && ch <= '9') ret = ret * 10 + ch - '0', ch = getc();
        return ret*p;
    }
    inline void flush(){ fwrite(out, 1, ptr - out, stdout); ptr = out; }
    template <typename T> inline void write(T x, char cmd = '\n'){
        if(x < 0) *ptr++ = '-', x = -x;
        if(x == 0) *ptr++ = '0';
        static char s[123]; int cnt = 0;
        for(; x; x /= 10) s[++cnt] = x % 10 + '0';
        for(; cnt; --cnt) *ptr++ = s[cnt];
        *ptr++ = cmd;
        if((outsiz >> 1) > ptr - out) flush();
    }
} using IO::getc; using IO::read; using IO::write; using IO::flush;

const int maxn = 212345;
struct edge{
	int v, nxt;
}e[maxn << 1];
int fir[maxn], num(1);
inline void add(int u, int v){
	e[++num].v = v; e[num].nxt = fir[u]; fir[u] = num;
}
bool asked[maxn]; 
int main(){
	int n = read<int>();
	for(int i(1), u, v; i < n; ++i){
		u = read<int>(); v = read<int>();
		add(u, v); add(v, u);
	}
	std::queue<int> q;
	q.push(1); asked[1] = true; int las = 1;
	while(!q.empty()){
		las = q.front(); q.pop();
		for(int itr(fir[las]), v; itr; itr = e[itr].nxt){
			if(asked[v = e[itr].v]) continue;
			q.push(v); asked[v] = true;
		}
	}
	memset(asked, 0, sizeof(asked));
	int len = 0; asked[las] = true; q.push(las);
	while(!q.empty()){
		int l = q.size(); ++len;
		while(l--){
			int now = q.front(); q.pop();
			for(int itr(fir[now]), v; itr; itr = e[itr].nxt){
				if(asked[v = e[itr].v]) continue;
				q.push(v); asked[v] = true;
			}
		}
	}
	printf("%s\n", len%3 == 2 ? "Second" : "First");
	flush(); return 0;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:60:9: error: 'memset' was not declared in this scope
   60 |         memset(asked, 0, sizeof(asked));
      |         ^~~~~~
a.cc:6:1: note: 'memset' is defined in header '<cstring>'; this is probably fixable by adding '#include <cstring>'
    5 | #include <queue>
  +++ |+#include <cstring>
    6 |
Language: C++

#include <bits/stdc++.h>
using namespace std;
const int maxn = 2e5+5;
vector<int> edge[maxn];
int dep[maxn];
int n;

void dfs(int u, int pre) {
    for (auto v :edge[u]) {
        if (v == pre) continue;
        dep[v] = dep[u] + 1;
        dfs(v, u);
    }
}

int main() {
    cin >>n;
    if (n == 1) {
        cout << "First" << endl;
        return;
    }
    for (int i = 1, u, v; i < n; ++i) {
        cin >> u>> v;
        edge[u].push_back(v);
        edge[v].push_back(u);
    }
    dfs(1,0);
    sort(dep + 1, dep +1 +n);
    int res = (dep[n] + dep[n- 1]) % 3;
    if (res == 0) cout << "Second" <<endl;
    else cout <<"First"<<endl;
    return 0;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:20:9: error: return-statement with no value, in function returning 'int' [-fpermissive]
   20 |         return;
      |         ^~~~~~
Language: C++

#include<bits/stdc++.h>
using namespace std;
#define rep(i,n) for(int i=0;i<n;i++)
int n,a,b,c,e=0,r[200001]={0},d[200001]={0};
vector<int> A(200001);
int search(int x){
  r[x]=1;
  for(auto i:A[x]) if(!r[i]) d[i]=d[x]+1,search(i);
}
int main(){
  cin>>n;
  rep(i,n-1) cin>>a>>b,A[a].push_back(b),A[b].push_back(a);
  search(1);
  rep(i,n) if(d[i+1]>e) e=d[i+1],c=i+1;
  rep(i,n) r[i+1]=0;
  d[c]=0,search(c);
  rep(i,n) if(d[i+1]>e) e=d[i+1],c=i+1;
  if(e%3==1) cout<<"Second";
  else cout<<"First";
}


Compiler output:
a.cc: In function 'int search(int)':
a.cc:8:17: error: 'begin' was not declared in this scope
    8 |   for(auto i:A[x]) if(!r[i]) d[i]=d[x]+1,search(i);
      |                 ^
a.cc:8:17: note: suggested alternatives:
In file included from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:166,
                 from a.cc:1:
/usr/include/c++/14/valarray:1238:5: note:   'std::begin'
 1238 |     begin(const valarray<_Tp>& __va) noexcept
      |     ^~~~~
In file included from /usr/include/c++/14/filesystem:53,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:200:
/usr/include/c++/14/bits/fs_dir.h:608:3: note:   'std::filesystem::__cxx11::begin'
  608 |   begin(recursive_directory_iterator __iter) noexcept
      |   ^~~~~
a.cc:8:17: error: 'end' was not declared in this scope
    8 |   for(auto i:A[x]) if(!r[i]) d[i]=d[x]+1,search(i);
      |                 ^
a.cc:8:17: note: suggested alternatives:
/usr/include/c++/14/valarray:1265:5: note:   'std::end'
 1265 |     end(const valarray<_Tp>& __va) noexcept
      |     ^~~
/usr/include/c++/14/bits/fs_dir.h:613:3: note:   'std::filesystem::__cxx11::end'
  613 |   end(recursive_directory_iterator) noexcept
      |   ^~~
a.cc:9:1: warning: no return statement in function returning non-void [-Wreturn-type]
    9 | }
      | ^
a.cc: In function 'int main()':
a.cc:12:29: error: request for member 'push_back' in 'A.std::vector<int>::operator[](((std::vector<int>::size_type)a))', which is of non-class type '__gnu_cxx::__alloc_traits<std::allocator<int>, int>::value_type' {aka 'int'}
   12 |   rep(i,n-1) cin>>a>>b,A[a].push_back(b),A[b].push_back(a);
      |                             ^~~~~~~~~
a.cc:12:47: error: request for member 'push_back' in 'A.std::vector<int>::operator[](((std::vector<int>::size_type)b))', which is of non-class type '__gnu_cxx::__alloc_traits<std::allocator<int>, int>::value_type' {aka 'int'}
   12 |   rep(i,n-1) cin>>a>>b,A[a].push_back(b),A[b].push_back(a);
      |                                               ^~~~~~~~~
Language: C++

#include<iostream.h>

using namespace std;

int main()
{
  int n; 
  cin >> n;
  if (n&1) cout << "First";
  else cout << "Second";
    return 0;
}

Compiler output:
a.cc:1:9: fatal error: iostream.h: No such file or directory
    1 | #include<iostream.h>
      |         ^~~~~~~~~~~~
compilation terminated.
Language: C++

#include <bits/stdc++.h>
using namespace std;
typedef pair<int, int> ii;
typedef vector<int> vi;
const int INF=1e9;


int N;
vi G[100001];
int d[100001];

ii dijkstra(int s){
  memset(d, INF, sizeof(d));
  priority_queue<ii, vector<ii>, greater<ii>> que;
  d[s]=0;
  que.push({d[s], s});
  while(!que.empty()){
    ii p=que.top();que.pop();
    int v=p.second;
    if(d[v]<p.first) continue;
    int M=G[v].size();
    for (int i=0;i<M;++i){
      int nv=G[v][i];
      if(d[nv]>v.first+1){
        d[nv]=v.first+1;
        que.push({d[nv], nv});
      }
    }
  }

  int dist=0, ans=s;
  for (int i=0;i<N;++i){
    if(dist<d[i]){dist=d[i];ans=i;}
  }
  return {dist, ans};
}

int tree_diam(){
  ii p=dijkstra(s);
  int u=p.second;
  ii q=dijkstra(u);
  int ans=q.first;
  return ans; 
}

int main(){
  cin>>N;
  for (int i=0;i<N-1;++i){
    int a,b;cin>>a>>b;
    G[a].push_back(b);G[b].push_back(a);
  }

  int L=tree_diam();
  if(L%3==0) cout << "Second" << endl;
  else cout << "First" << endl;
  return 0;
}

Compiler output:
a.cc: In function 'ii dijkstra(int)':
a.cc:24:18: error: request for member 'first' in 'v', which is of non-class type 'int'
   24 |       if(d[nv]>v.first+1){
      |                  ^~~~~
a.cc:25:17: error: request for member 'first' in 'v', which is of non-class type 'int'
   25 |         d[nv]=v.first+1;
      |                 ^~~~~
a.cc: In function 'int tree_diam()':
a.cc:39:17: error: 's' was not declared in this scope
   39 |   ii p=dijkstra(s);
      |                 ^
Language: C++

#include <bits/stdc++.h>
using namespace std;
typedef pair<int, int> ii;
const int INF=1e9;


int N;
vi G[100001];
int d[100001];

ii dijkstra(int s){
  memset(d, INF, sizeof(d));
  priority_queue<ii, vector<ii>, greater<ii>> que;
  d[s]=0;
  que.push({d[s], s});
  while(!que.empty()){
    ii p=que.top();que.pop();
    int v=p.second;
    if(d[v]<p.first) continue;
    int M=G[v].size();
    for (int i=0;i<M;++i){
      int nv=G[v][i];
      if(d[nv]>v.first+1){
        d[nv]=v.first+1;
        que.push({d[nv], nv});
      }
    }
  }

  int dist=0, ans=s;
  for (int i=0;i<N;++i){
    if(dist<d[i]){dist=d[i];ans=i;}
  }
  return {dist, ans};
}

int tree_diam(){
  ii p=dijkstra(s);
  int u=p.second;
  ii q=dijkstra(u);
  int ans=q.first;
  return ans; 
}

int main(){
  cin>>N;
  for (int i=0;i<N-1;++i){
    int a,b;cin>>a>>b;
    G[a].push_back(b);G[b].push_back(a);
  }

  int L=tree_diam();
  if(L%3==0) cout << "Second" << endl;
  else cout << "First" << endl;
  return 0;
}

Compiler output:
a.cc:8:1: error: 'vi' does not name a type; did you mean 'ii'?
    8 | vi G[100001];
      | ^~
      | ii
a.cc: In function 'ii dijkstra(int)':
a.cc:20:11: error: 'G' was not declared in this scope
   20 |     int M=G[v].size();
      |           ^
a.cc:23:18: error: request for member 'first' in 'v', which is of non-class type 'int'
   23 |       if(d[nv]>v.first+1){
      |                  ^~~~~
a.cc:24:17: error: request for member 'first' in 'v', which is of non-class type 'int'
   24 |         d[nv]=v.first+1;
      |                 ^~~~~
a.cc: In function 'int tree_diam()':
a.cc:38:17: error: 's' was not declared in this scope
   38 |   ii p=dijkstra(s);
      |                 ^
a.cc: In function 'int main()':
a.cc:49:5: error: 'G' was not declared in this scope
   49 |     G[a].push_back(b);G[b].push_back(a);
      |     ^
Language: C++

#include <bits/stdc++.h>
using namespace std;
typedef pair<int, int> ii;
const int INF=1e9;


int N;
vi G[100001];
int d[100001];

ii dijkstra(int s){
  memset(d, INF, sizeof(d));
  priority_queue<ii, vector<ii>, greater<ii>> que;
  d[s]=0;
  que.push({d[s], s});
  while(!que.empty()){
    ii p=que.top();que.pop();
    int v=p.second;
    if(d[v]<v.first) continue;
    int M=G[v].size();
    for (int i=0;i<M;++i){
      int nv=G[v][i];
      if(d[nv]>v.first+1){
        d[nv]=v.first+1;
        que.push({d[nv], nv});
      }
    }
  }

  int dist=0, ans=s;
  for (int i=0;i<N;++i){
    if(dist<d[i]){dist=d[i];ans=i;}
  }
  return {dist, ans};
}

int tree_diam(){
  ii p=dijkstra(s);
  int u=p.second;
  ii q=dijkstra(u);
  int ans=q.first;
  return ans; 
}

int main(){
  cin>>N;
  for (int i=0;i<N-1;++i){
    int a,b;cin>>a>>b;
    G[a].push_back(b);G[b].push_back(a);
  }

  int L=tree_diam();
  if(L%3==0) cout << "Second" << endl;
  else cout << "First" << endl;
  return 0;
}

Compiler output:
a.cc:8:1: error: 'vi' does not name a type; did you mean 'ii'?
    8 | vi G[100001];
      | ^~
      | ii
a.cc: In function 'ii dijkstra(int)':
a.cc:19:15: error: request for member 'first' in 'v', which is of non-class type 'int'
   19 |     if(d[v]<v.first) continue;
      |               ^~~~~
a.cc:20:11: error: 'G' was not declared in this scope
   20 |     int M=G[v].size();
      |           ^
a.cc:23:18: error: request for member 'first' in 'v', which is of non-class type 'int'
   23 |       if(d[nv]>v.first+1){
      |                  ^~~~~
a.cc:24:17: error: request for member 'first' in 'v', which is of non-class type 'int'
   24 |         d[nv]=v.first+1;
      |                 ^~~~~
a.cc: In function 'int tree_diam()':
a.cc:38:17: error: 's' was not declared in this scope
   38 |   ii p=dijkstra(s);
      |                 ^
a.cc: In function 'int main()':
a.cc:49:5: error: 'G' was not declared in this scope
   49 |     G[a].push_back(b);G[b].push_back(a);
      |     ^
Language: C++

#include <bits/stdc++.h>
using namespace std;
typedef pair<int, int> ii;
const int INF=1e9;


int N;
vi G[N];
int d[N];

ii dijkstra(int s){
  memset(d, INF, sizeof(d));
  priority_queue<ii, vector<ii>, greater<ii>> que;
  d[s]=0;
  que.push({d[s], s});
  while(!que.empty()){
    ii p=que.top();que.pop();
    int v=p.second;
    if(d[v]<v.first) continue;
    int M=G[v].size();
    for (int i=0;i<M;++i){
      int nv=G[v][i];
      if(d[nv]>v.first+1){
        d[nv]=v.first+1;
        que.push({d[nv], nv});
      }
    }
  }

  int dist=0, ans=s;
  for (int i=0;i<N;++i){
    if(dist<d[i]){dist=d[i];ans=i;}
  }
  return {dist, ans};
}

int tree_diam(){
  ii p=dijkstra(s);
  int u=p.second;
  ii q=dijkstra(u);
  int ans=q.first;
  return ans; 
}

int main(){
  cin>>N;
  for (int i=0;i<N-1;++i){
    int a,b;cin>>a>>b;
    G[a].push_back(b);G[b].push_back(a);
  }

  int L=tree_diam();
  if(L%3==0) cout << "Second" << endl;
  else cout << "First" << endl;
  return 0;
}

Compiler output:
a.cc:8:1: error: 'vi' does not name a type; did you mean 'ii'?
    8 | vi G[N];
      | ^~
      | ii
a.cc:9:7: error: size of array 'd' is not an integral constant-expression
    9 | int d[N];
      |       ^
a.cc: In function 'ii dijkstra(int)':
a.cc:19:15: error: request for member 'first' in 'v', which is of non-class type 'int'
   19 |     if(d[v]<v.first) continue;
      |               ^~~~~
a.cc:20:11: error: 'G' was not declared in this scope
   20 |     int M=G[v].size();
      |           ^
a.cc:23:18: error: request for member 'first' in 'v', which is of non-class type 'int'
   23 |       if(d[nv]>v.first+1){
      |                  ^~~~~
a.cc:24:17: error: request for member 'first' in 'v', which is of non-class type 'int'
   24 |         d[nv]=v.first+1;
      |                 ^~~~~
a.cc: In function 'int tree_diam()':
a.cc:38:17: error: 's' was not declared in this scope
   38 |   ii p=dijkstra(s);
      |                 ^
a.cc: In function 'int main()':
a.cc:49:5: error: 'G' was not declared in this scope
   49 |     G[a].push_back(b);G[b].push_back(a);
      |     ^
Language: C++

#include <iostream>
#include <vector>

using namespace std;

vector<int> graph[200000];
vector<int> used(200000, 0);

int dfs(int node, int depth) {
    used[node] = 1;
    int ret = depth;
    for(int next_node: graph[node]) {
        if(used[next_node]) continue;
        ret = max(ret, dfs(next_node, depth+1));
    }
    return ret;
}

int calc_diameter() {
    vector<int> depths;
    used[0] = 1;
    for(int node: graph[0]) {
        depths.push_back(dfs(node, 1));
    }
    sort(depths.rbegin(), depths.rend());
    return depths[0]+depths[1];
}

int main() {
    std::ios::sync_with_stdio(0); cin.tie(0);
    int n, a, b;
    cin >> n;

    vector<int> degree(n, 0);
    for(int i=0;i<n-1;++i) {
        cin >> a >> b;
        --a; --b;
        graph[a].push_back(b);
        graph[b].push_back(a);
    }

    if(calc_diameter() % 3 != 1) {
        cout << "First\n";
    } else {
        cout << "Second\n";
    }

}


Compiler output:
a.cc: In function 'int calc_diameter()':
a.cc:25:5: error: 'sort' was not declared in this scope; did you mean 'short'?
   25 |     sort(depths.rbegin(), depths.rend());
      |     ^~~~
      |     short
Language: C++

fsd#include <bits/stdc++.h>

using namespace std;

#define fi first
#define se second
#define pb push_back
#define mp make_pair
#define all(a) a.begin(), a.end()
#define rep(i, st, n) for (int i = (st); i < (n); ++i)

using ll = long long;
using ull = unsigned long long;
using pii = pair<int, int>;
using pll = pair<long long, long long>;
using ld = long double;

template <typename T1, typename T2> bool chkmin(T1 &x, T2 y) { return y < x ? (x = y, true) : false; }
template <typename T1, typename T2> bool chkmax(T1 &x, T2 y) { return y > x ? (x = y, true) : false; }

vector<int> G[200005];
int diam;
int dfs(int v, int pr = -1)
{
    int mx1 = 1;
    int mx2 = 0;
    for (int u : G[v]) if (u != pr)
    {
        int l = dfs(u, v) + 1;
        if (l >= mx1)
        {
            mx2 = mx1;
            mx1 = l;
        }
        else chkmax(mx2, l);
    }
    chkmax(diam, mx1);
    chkmax(diam, mx1 + mx2 - 1);
    return mx1;
}

signed main()
{
#ifdef DEBUG
    freopen("in", "r", stdin);
#endif
    ios::sync_with_stdio(0);
    cin.tie(0);
    
    int n;
    cin >> n;
    for (int i = 0; i < n - 1; ++i)
    {
        int v, u;
        cin >> v >> u;
        G[v].pb(u);
        G[u].pb(v);
    }
    diam = 1;
    dfs(1);
    vector<char> win(diam + 1);
    win[0] = false;
    win[1] = true;
    win[2] = false;
    for (int i = 3; i <= diam; ++i)
        win[i] = !win[i - 1] || !win[i - 2];
    cout << (win[diam] ? "First\n" : "Second\n");
    
    return 0;
}

Compiler output:
a.cc:1:4: error: stray '#' in program
    1 | fsd#include <bits/stdc++.h>
      |    ^
a.cc:1:1: error: 'fsd' does not name a type
    1 | fsd#include <bits/stdc++.h>
      | ^~~
a.cc:14:13: error: 'pair' does not name a type
   14 | using pii = pair<int, int>;
      |             ^~~~
a.cc:15:13: error: 'pair' does not name a type
   15 | using pll = pair<long long, long long>;
      |             ^~~~
a.cc:21:1: error: 'vector' does not name a type
   21 | vector<int> G[200005];
      | ^~~~~~
a.cc: In function 'int dfs(int, int)':
a.cc:27:18: error: 'G' was not declared in this scope
   27 |     for (int u : G[v]) if (u != pr)
      |                  ^
a.cc: In function 'int main()':
a.cc:47:5: error: 'ios' has not been declared
   47 |     ios::sync_with_stdio(0);
      |     ^~~
a.cc:48:5: error: 'cin' was not declared in this scope
   48 |     cin.tie(0);
      |     ^~~
a.cc:56:9: error: 'G' was not declared in this scope
   56 |         G[v].pb(u);
      |         ^
a.cc:61:5: error: 'vector' was not declared in this scope
   61 |     vector<char> win(diam + 1);
      |     ^~~~~~
a.cc:61:12: error: expected primary-expression before 'char'
   61 |     vector<char> win(diam + 1);
      |            ^~~~
a.cc:62:5: error: 'win' was not declared in this scope
   62 |     win[0] = false;
      |     ^~~
a.cc:67:5: error: 'cout' was not declared in this scope
   67 |     cout << (win[diam] ? "First\n" : "Second\n");
      |     ^~~~
Language: C++

//
//  atcoder.cpp
//
//
///
#include <bits/stdc++.h>
#define REP(i, N) for(int i=0; i<N; i++)
using namespace std;
 
//#include "atcoder.hpp"
 
long long gcd(long long a, long long b) {
    if (a>b) swap(a,b);
    
    auto r = b % a;
    
    return (r ? gcd(r, a) : a);
}
 
int main() {
    int N;
    cin>>N;
    vector<vector<int>> ab(N+1);
    
 
    for (int i = 0; i < N-1; i++) {
        int a, b;
        cin >> a >> b;
        
        ab[a].push_back(b);
        ab[b].push_back(a);
    }
    vector<int> cache(N+1, -1);
    
    auto solve = [&](auto f, int i) {
        auto cached = 0;
        
        if (cache[i] >= 0)
            return 0;
      cache[i] = 0;
        for (auto j : ab[i]) {
            cached = max(cached, f(f, j));
        }
        cache[i] = cached + 1;
        return cached;
    };
    
    
    cout << ((solve(solve, 1) % 3) == 1) ? "First" : "Second") << endl;
    
    return 0;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:49:62: error: expected ';' before ')' token
   49 |     cout << ((solve(solve, 1) % 3) == 1) ? "First" : "Second") << endl;
      |                                                              ^
      |                                                              ;
Language: C++

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

int n;
vector<int> adj[200000];

array<int, 2> dfs(int u, int p=-1, int d=1) {
	array<int, 2> r={d, u};
	for(int v : adj[u])
		if(v^p)
			r=max(dfs(v, u, d+1), r);
	return r;
}

int main() {
	ios::sync_with_stdio(0);
	cin.tie(0);

	cin >> n;
	for(int i = 1, a, b; i < n; i++) {
		cin >> a >> b;
		--a;
		--b;
		adj[a].push_back(b);
		adj[b].push_back(a);
	}
	cout << (dfs(dfs(0).second).first%3 == 2 ? "Second" : "First");
}

Compiler output:
a.cc: In function 'int main()':
a.cc:27:29: error: 'struct std::array<int, 2>' has no member named 'second'
   27 |         cout << (dfs(dfs(0).second).first%3 == 2 ? "Second" : "First");
      |                             ^~~~~~
Language: C++

#include <iostream>
#include <vector>
#include <algorithm>
#include <string>
#include <map>
#include <set>
#include <queue>
using namespace std;

typedef long long ll;
typedef unsigned long long ull;

int main()
{
    ll N;
    cin >> N;
    int ai, bi;
    vector<vector<int>> G(N, vector<int>());
    for(int i=0;i<N-1;i++){
        cin >> ai >> bi;
        G[ai-1].push_back(bi-1);
        G[bi-1].push_back(ai-1);
    }
    queue<pair<int,int>> q_end;
    vector<int> visited(N, INT_MIN);
    for(size_t i=0; i<G.size(); i++){
        if(G[i].size()==1){
            q_end.push(make_pair<int,int>(i,-1));
            visited[i] = 1;
        }
    }

    while(!q_end.empty()){
        queue<pair<int,int>> q_next;
        while(!q_end.empty()){
            auto v = q_end.front(); q_end.pop();
            for(auto g : G[v.first]){
                if(g==v.second) continue;
                if(visited[g] <= visited[v.first]){
                    q_next.push(make_pair(g,v.first));
                    visited[g] = visited[v.first]+1;
                }
            }
        }
        q_end = q_next;
    }
    int nmax = 0;
    int cmax = 0;
    for(auto v : visited){
        if(v == nmax) cmax++;
        else if(v > nmax){
            nmax = v;
            cmax = 1;
        }
    }
    if((nmax-0)%3==2) cout<<"Second"<<endl;
    else              cout<<"First"<<endl;

    return 0;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:25:28: error: 'INT_MIN' was not declared in this scope
   25 |     vector<int> visited(N, INT_MIN);
      |                            ^~~~~~~
a.cc:8:1: note: 'INT_MIN' is defined in header '<climits>'; this is probably fixable by adding '#include <climits>'
    7 | #include <queue>
  +++ |+#include <climits>
    8 | using namespace std;
Language: C++

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

// This class represents a undirected graph using adjacency list 
class Graph
{
	int V;              // No. of vertices 
	list<int> *adj;     // Pointer to an array containing 
						// adjacency lists 
public:
	Graph(int V);              // Constructor 
	void addEdge(int v, int w);// function to add an edge to graph 
	void longestPathLength();  // prints longest path of the tree 
	pair<int, int> bfs(int u); // function returns maximum distant 
							   // node from u with its distance 
};

Graph::Graph(int V)
{
	this->V = V;
	adj = new list<int>[V];
}

void Graph::addEdge(int v, int w)
{
	adj[v].push_back(w);    // Add w to v’s list. 
	adj[w].push_back(v);    // Since the graph is undirected 
}

//  method returns farthest node and its distance from node u 
pair<int, int> Graph::bfs(int u)
{
	//  mark all distance with -1 
	int dis[V];
	memset(dis, -1, sizeof(dis));

	queue<int> q;
	q.push(u);

	//  distance of u from u will be 0 
	dis[u] = 0;

	while (!q.empty())
	{
		int t = q.front();       q.pop();

		//  loop for all adjacent nodes of node-t 
		for (auto it = adj[t].begin(); it != adj[t].end(); it++)
		{
			int v = *it;

			// push node into queue only if 
			// it is not visited already 
			if (dis[v] == -1)
			{
				q.push(v);

				// make distance of v, one more 
				// than distance of t 
				dis[v] = dis[t] + 1;
			}
		}
	}

	int maxDis = 0;
	int nodeIdx;

	//  get farthest node distance and its index 
	for (int i = 0; i < V; i++)
	{
		if (dis[i] > maxDis)
		{
			maxDis = dis[i];
			nodeIdx = i;
		}
	}
	return make_pair(nodeIdx, maxDis);
}

//  method prints longest path of given tree 
void Graph::longestPathLength()
{
	pair<int, int> t1, t2;

	// first bfs to find one end point of 
	// longest path 
	t1 = bfs(0);

	//  second bfs to find actual longest path 
	t2 = bfs(t1.first);

	cout << "Longest path is from " << t1.first << " to "
		<< t2.first << " of length " << t2.second;
}

// Driver code to test above methods 
int main()
{
	int N; cin >> N;
	// Create a graph given in the example 
	Graph g(N);
	for (int i = 0; i < N - 1; i++) {
		int x, y;
		cin >> x >> y;
		g.addEdge(x, y);
	}
	if (g.longestPathLength() % 3 == 2) {
		cout << "Second";
	}
	else {
		cout << "First";
	}
	return 0;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:107:35: error: invalid operands of types 'void' and 'int' to binary 'operator%'
  107 |         if (g.longestPathLength() % 3 == 2) {
      |             ~~~~~~~~~~~~~~~~~~~~~ ^ ~
      |                                |    |
      |                                void int
Language: C++

木の最長経路がmod3 で2

Compiler output:
a.cc:1:1: error: '\U00006728\U0000306e\U00006700\U00009577\U00007d4c\U00008def\U0000304cmod3' does not name a type
    1 | 木の最長経路がmod3 で2
      | ^~~~~~~~~~~~~~~~~~
Language: C++

#include <iostream>
using namespace std;
int main(){
  cin>>n;
  if(n%2==0)cout<<"Second"<<endl;
  else cout<<"First"<<endl;
  return 0;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:4:8: error: 'n' was not declared in this scope
    4 |   cin>>n;
      |        ^
Language: C++

#include<iostream>
#include<cstdio>
#include<queue>
#include<vector>


#define MAX 1000000
#define INFTY (1 << 30) 
using namespace std;
typedef long long int ll;

class Edge{
public:
	ll t,w;
	Edge(){}
	Edge(ll t, ll w): t(t), w(w) {}
};

vector<Edge> G[MAX];
ll n, d[MAX];

bool vis[MAX];
ll cnt;

void bfs(ll s){
for(ll i=0;i<n;i++) d[i]=INFTY;
queue<ll> Q;
Q.push(s);
d[s]=0;
ll u;
while( !Q,empty()){
u=Q.front();Q.pop();
for(ll i=0;i<G[u].size();i++){
Edge e=G[u][i];
if(d[e.t] == INFTY){
d[e.t]=d[u]+e.w;
Q.push(e.t);
}
}
}
}

void solve(){
bfs(0);
ll maxv=0;
ll tgt=0;
for( ll i=0;i<n;i++){
if(d[i]==INFTY) continue;
if (maxv<d[i]){
maxv=d[i];
tgt=i;
}
}

bfs(tgt);;
maxv=0;
for (ll i=0;i<n;i++){
if(d[i] == INFTY) continue;
maxv=max(maxv,d[i]);
}

if(maxv%3==1)
{	printf("Second");
}
else
{
	printf("First");
}
};

int main()
{	ll w=1;

	cin >> n;
	ll s, t;
	for(ll i=0;i<n-1;i++){
		cin >> s >> t;
	
		G[s].push_back(Edge(t,w));
		G[t].push_back(Edge(s,w));
	}
	solve();
	
}



Compiler output:
a.cc: In function 'void bfs(ll)':
a.cc:31:8: error: no match for 'operator!' (operand type is 'std::queue<long long int>')
   31 | while( !Q,empty()){
      |        ^~
a.cc:31:8: note: candidate: 'operator!(bool)' (built-in)
a.cc:31:8: note:   no known conversion for argument 1 from 'std::queue<long long int>' to 'bool'
a.cc:31:16: error: no matching function for call to 'empty()'
   31 | while( !Q,empty()){
      |           ~~~~~^~
In file included from /usr/include/c++/14/string:53,
                 from /usr/include/c++/14/bits/locale_classes.h:40,
                 from /usr/include/c++/14/bits/ios_base.h:41,
                 from /usr/include/c++/14/ios:44,
                 from /usr/include/c++/14/ostream:40,
                 from /usr/include/c++/14/iostream:41,
                 from a.cc:1:
/usr/include/c++/14/bits/range_access.h:282:5: note: candidate: 'template<class _Container> constexpr decltype (__cont.empty()) std::empty(const _Container&)'
  282 |     empty(const _Container& __cont) noexcept(noexcept(__cont.empty()))
      |     ^~~~~
/usr/include/c++/14/bits/range_access.h:282:5: note:   candidate expects 1 argument, 0 provided
/usr/include/c++/14/bits/range_access.h:292:5: note: candidate: 'template<class _Tp, long unsigned int _Nm> constexpr bool std::empty(const _Tp (&)[_Nm])'
  292 |     empty(const _Tp (&)[_Nm]) noexcept
      |     ^~~~~
/usr/include/c++/14/bits/range_access.h:292:5: note:   candidate expects 1 argument, 0 provided
/usr/include/c++/14/bits/range_access.h:302:5: note: candidate: 'template<class _Tp> constexpr bool std::empty(initializer_list<_Tp>)'
  302 |     empty(initializer_list<_Tp> __il) noexcept
      |     ^~~~~
/usr/include/c++/14/bits/range_access.h:302:5: note:   candidate expects 1 argument, 0 provided
Language: C

#include<stdio.h>
int main(void)
{
	int n;
  int a[200000];
  int b[200000];
  int i;
  
  for(i=0;i<n;i++)
  {
    scanf("%d",&a[i]);
    scanf("%d",&b[i]);
  ]
  if(n%2==1)
    printf("First");
  else
    printf("Second");
    
    return 0;
  
}

Compiler output:
main.c: In function 'main':
main.c:13:3: error: expected statement before ']' token
   13 |   ]
      |   ^
main.c:21:1: error: expected declaration or statement at end of input
   21 | }
      | ^
Language: C++

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

int main() {
  int n;
  cin >> n;
  
  if(n % 2 == 1){
    cout << "First" << endl;
  }
  else{
    cout < "Second" << endl;
  }
}

Compiler output:
a.cc: In function 'int main()':
a.cc:12:21: error: invalid operands of types 'const char [7]' and '<unresolved overloaded function type>' to binary 'operator<<'
   12 |     cout < "Second" << endl;
      |            ~~~~~~~~~^~~~~~~
Language: C++

#include <stdio.h>
#include <vector>
using namespace std;
const int N=2e5+10;
#define PB push_back
vector<int> graph[N];
int dep[N];
void dfs(int now){
  for(int i:graph[now])if(dep[i]==-1){
    dep[i]=dep[now]+1;
    dfs(i);
  }
  return ;
}
int max(int a,int b){return a>b?a:b;}
int main(){
  int n,l,r,root=1,ans=0;
  scanf("%d",&n);
  for(int i=1;i<n;i++){
	scanf("%d%d",&l,&r);
    graph[l].PB(r);
    grpah[r].PB(l);
  }
  dep[1]=1;
  for(int i=2;i<=n;i++)dep[i]=-1;
  dfs(1);
  for(int i=1;i<=n;i++)if(dep[i]>dep[root])root=i;
  for(int i=1;i<=n;i++)dep[i]=-1;
  dep[root]=1;
  dfs(root);
  for(int i=1;i<=n;i++)ans=max(ans,dep[i]);
  if(ans%3==2)printf("Second\n");
  else printf("First\n");
}

Compiler output:
a.cc: In function 'int main()':
a.cc:22:5: error: 'grpah' was not declared in this scope; did you mean 'graph'?
   22 |     grpah[r].PB(l);
      |     ^~~~~
      |     graph
Language: C++

#include <vector>
#include <iostream> 
using namespace std;

vector<vector<int>> edge;

void dfs(int idx, int y, int d, vector<int> &vv) {
    if (vv[idx] >= 0) return;
    vv[idx] = d;
    for(int x: edge[idx]) {
        if (x == y) continue;
        dfs(x, idx, d+1, vv);
    }
}


void mainmain(){
    int N;
    cin >> N;
    edge = vector<vector<int>>(N);
    for(int i=0; i<N; i++) {
        int a,b;
        cin >> a >> b;
        a--,b--;
        edge[a].push_back(b);
        edge[b].push_back(a);
    }
    vector<int> vv(N, -1);
    dfs(0, -1, 0, vv);
    int idx = 0;
    for(int i=0; i<N; i++) {
        if (vv[idx] < vv[i]) {
            idx = i;
        }
    }
    vv = vector<int>(N, -1);
    dfs(idx, -1, 0, vv);
    int mx = 0;
    for(int i=0; i<N; i++) {
        mx = max(mx, vv[i]);
    }
    cout << (mx % 3 == 1 ? "Second" : "First") << endl;
}
 
 
signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout<<fixed<<setprecision(20);
    mainmain();
}

Compiler output:
a.cc: In function 'int main()':
a.cc:49:18: error: 'setprecision' was not declared in this scope
   49 |     cout<<fixed<<setprecision(20);
      |                  ^~~~~~~~~~~~
a.cc:3:1: note: 'std::setprecision' is defined in header '<iomanip>'; this is probably fixable by adding '#include <iomanip>'
    2 | #include <iostream>
  +++ |+#include <iomanip>
    3 | using namespace std;
Language: C++

#include <bits/stdc++.h>

int main(){
 int N;
  cin >> N;
  if(N%2==0){
    cout << "Second" << endl;
  }else{
    cout << "First" << endl;
  }
  return 0;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:5:3: error: 'cin' was not declared in this scope; did you mean 'std::cin'?
    5 |   cin >> N;
      |   ^~~
      |   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
      |                  ^~~
a.cc:7:5: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
    7 |     cout << "Second" << 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:7:25: error: 'endl' was not declared in this scope; did you mean 'std::endl'?
    7 |     cout << "Second" << endl;
      |                         ^~~~
      |                         std::endl
In file included from /usr/include/c++/14/istream:41,
                 from /usr/include/c++/14/sstream:40,
                 from /usr/include/c++/14/complex:45,
                 from /usr/include/c++/14/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:127:
/usr/include/c++/14/ostream:744:5: note: 'std::endl' declared here
  744 |     endl(basic_ostream<_CharT, _Traits>& __os)
      |     ^~~~
a.cc:9:5: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
    9 |     cout << "First" << 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:9:24: error: 'endl' was not declared in this scope; did you mean 'std::endl'?
    9 |     cout << "First" << endl;
      |                        ^~~~
      |                        std::endl
/usr/include/c++/14/ostream:744:5: note: 'std::endl' declared here
  744 |     endl(basic_ostream<_CharT, _Traits>& __os)
      |     ^~~~
Language: C++

#include <bits/stdc++.h>
const int N=190;
using std::max;
using std::min;
int n,m,a[N][N],sum[N][N],dp[N][N][N][15];
char c[N][N];
int main(){
    scanf("%d%d",&n,&m);
    for (int i=1;i<=n;i++) scanf("%s",c[i]+1);
    for(int i=1;i<=n;i++)
        for(int j=1;j<=m;j++){
            if (c[i][j]=='.') a[i][j]=1;
            else a[i][j]=0;
            sum[i][j]=sum[i-1][j]+sum[i][j-1]-sum[i-1][j-1]+a[i][j];
        }
    for (int i=1;i<=n;i++)  
        for (int j=1;j<=m;j++)
            for (int k=j;k<=m;k++){
                int l=i,r=n,ans=i-1;
                while (l<=r){
                    int mid=(l+r)>>1;
                    int s=sum[mid][k]-sum[mid][j-1]-sum[i-1][k]+sum[i-1][j-1];
                    if (s==0 || s==(mid-i+1)*(k-j+1))
                        ans=mid,l=mid+1;
                    else r=mid-1;
                }
                dp[i][j][k][0]=ans;
            }
    int k=1;
    for (k=1;dp[1][1][m][k-1]<n;k++)
    for (int h=1;h<=m;h++)
        for (int i=1;i<=n;i++)
            for (int j1=1,j2=j1+h-1;j2<=m;j1++,j2++){
                    if (dp[i][j1][j2][k-1]==n){
                        dp[i][j1][j2][k]=n;
                        continue;
                    }
                    dp[i][j1][j2][k]=dp[dp[i][j1][j2][k-1]+1][j1][j2][k-1];//横
                    if(dp[i][j1][j2][k]==n) continue; 
                    int l=j1,r=j2-1,ans=0;//竖 
                    while (l<=r){
                        int mid=(l+r)>>1;
                        int x=dp[i][j1][mid][k-1],y=dp[i][mid+1][j2][k-1];
                        ans=max(ans,min(x,y));
                        if (x<y) r=mid-1;
                        else l=mid+1;
                    }
    
                    dp[i][j1][j2][k]=max(dp[i][j1][j2][k],ans);
                }
    printf("%d\n",k-1);

Compiler output:
a.cc: In function 'int main()':
a.cc:51:24: error: expected '}' at end of input
   51 |     printf("%d\n",k-1);
      |                        ^
a.cc:7:11: note: to match this '{'
    7 | int main(){
      |           ^
Language: C++

#include<bits/stdc++.h>
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define pb push_back
using namespace std;
using ll = long long;
using vi = vector<ll>;
using pi = pair<ll, ll>;
const int maxn = 190;//, mod = 1e9 + 7;
int n, m;
unsigned char xdp[17][maxn][maxn][maxn], ydp[17][maxn][maxn][maxn];
int mat[maxn][maxn];
int sum(int lx, int rx, int ly, int ry) {
	lx--, ly--;
	return mat[rx][ry] - mat[lx][ry] - mat[rx][ly] + mat[lx][ly];
}
bool good(int lx, int rx, int ly, int ry) {
	return sum(lx, rx, ly, ry)==0||sum(lx, rx, ly, ry)==(rx-lx+1)*(ry-ly+1);
}
int main() {
	ios::sync_with_stdio(0);
	cin.tie(0);
	cin >> n >> m;
	char t;
	for(int i = 1; i <= n; i++)
		for(int j = 1; j <= m; j++) {
			cin >> t;
			mat[i][j] = mat[i-1][j] + mat[i][j-1] - mat[i-1][j-1] + (t=='#');
		}
	for(int c = 0; c < 17; c++) {
		for(int lx = 1; lx <= n; lx++) {
			for(int rx = lx; rx <= n; rx++) {
				for(int y = 1; y <= m; y++) {
					char &t = xdp[c][lx][rx][y];
					if(c==0) {
						t = y;
						while(t <= m && good(lx, rx, y, t)) t++;
					} else {
						t = xdp[c-1][lx][rx][y];
						if(t<=m) t = xdp[c-1][lx][rx][t];
						while(t <= m) {
							int u = ydp[c-1][y][t][lx];
							if(u <= n) u = ydp[c-1][y][t][u];
							if(u>rx) t++;
							else break;
						}
					}
				}
			}
		}
		
		for(int ly = 1; ly <= m; ly++) {
			for(int ry = ly; ry <= m; ry++) {
				for(int x = 1; x <= n; x++) {
					char &t = ydp[c][ly][ry][x];
					if(!c) {
						t = x;
						while(t <= n && good(x, t, ly, ry)) t++;
					} else {
						t = ydp[c-1][ly][ry][x];
						if(t <= m) t = ydp[c-1][ly][ry][t];
						while(t <= m) {
							int u = xdp[c-1][x][t][ly];
							if(u <= n) u = xdp[c-1][x][t][u];
							if(u>ry) t++;
							else break;
						}
					}
				}
			}
		}
	}
	int ans = 0;
	while(ans < 17 && xdp[ans][1][n][1] <= m && ydp[ans][1][m][1] <= n) ans++;
	cout << ans;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:34:67: error: cannot bind non-const lvalue reference of type 'char&' to a value of type 'unsigned char'
   34 |                                         char &t = xdp[c][lx][rx][y];
      |                                                   ~~~~~~~~~~~~~~~~^
a.cc:55:67: error: cannot bind non-const lvalue reference of type 'char&' to a value of type 'unsigned char'
   55 |                                         char &t = ydp[c][ly][ry][x];
      |                                                   ~~~~~~~~~~~~~~~~^
Language: C++

#include<bits/stdc++.h>
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define pb push_back
using namespace std;
using ll = long long;
using vi = vector<ll>;
using pi = pair<ll, ll>;
const int maxn = 190;//, mod = 1e9 + 7;
int n, m;
char xdp[17][maxn][maxn][maxn], ydp[17][maxn][maxn][maxn];
int mat[maxn][maxn];
int sum(int lx, int rx, int ly, int ry) {
	lx--, ly--;
	return mat[rx][ry] - mat[lx][ry] - mat[rx][ly] + mat[lx][ly];
}
bool good(int lx, int rx, int ly, int ry) {
	return sum(lx, rx, ly, ry)==0||sum(lx, rx, ly, ry)==(rx-lx+1)*(ry-ly+1);
}
int main() {
	ios::sync_with_stdio(0);
	cin.tie(0);
	cin >> n >> m;
	char t;
	for(int i = 1; i <= n; i++)
		for(int j = 1; j <= m; j++) {
			cin >> t;
			mat[i][j] = mat[i-1][j] + mat[i][j-1] - mat[i-1][j-1] + (t=='#');
		}
	for(int c = 0; c < 17; c++) {
		for(int lx = 1; lx <= n; lx++) {
			for(int rx = lx; rx <= n; rx++) {
				for(int y = 1; y <= m; y++) {
					int &t = xdp[c][lx][rx][y];
					if(c==0) {
						t = y;
						while(t <= m && good(lx, rx, y, t)) t++;
					} else {
						t = xdp[c-1][lx][rx][y];
						if(t<=m) t = xdp[c-1][lx][rx][t];
						while(t <= m) {
							int u = ydp[c-1][y][t][lx];
							if(u <= n) u = ydp[c-1][y][t][u];
							if(u>rx) t++;
							else break;
						}
					}
				}
			}
		}
		
		for(int ly = 1; ly <= m; ly++) {
			for(int ry = ly; ry <= m; ry++) {
				for(int x = 1; x <= n; x++) {
					int &t = ydp[c][ly][ry][x];
					if(!c) {
						t = x;
						while(t <= n && good(x, t, ly, ry)) t++;
					} else {
						t = ydp[c-1][ly][ry][x];
						if(t <= m) t = ydp[c-1][ly][ry][t];
						while(t <= m) {
							int u = xdp[c-1][x][t][ly];
							if(u <= n) u = xdp[c-1][x][t][u];
							if(u>ry) t++;
							else break;
						}
					}
				}
			}
		}
	}
	int ans = 0;
	while(ans < 17 && xdp[ans][1][n][1] <= m && ydp[ans][1][m][1] <= n) ans++;
	cout << ans;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:34:66: error: cannot bind non-const lvalue reference of type 'int&' to a value of type 'char'
   34 |                                         int &t = xdp[c][lx][rx][y];
      |                                                  ~~~~~~~~~~~~~~~~^
a.cc:55:66: error: cannot bind non-const lvalue reference of type 'int&' to a value of type 'char'
   55 |                                         int &t = ydp[c][ly][ry][x];
      |                                                  ~~~~~~~~~~~~~~~~^