Peli

input/code.cpp: In function 'void bfs(int)':
input/code.cpp:32:30: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   32 |                 for(int j=0;j<e[u].size();j++)
      |                             ~^~~~~~~~~~~~

#include <bits/stdc++.h>

using namespace std;

const int N=2509;

int n,m,q;
int ans[N][N][2];
bool vst[N][2];

vector<int>e[N];

struct Node{
	int u,p;
};

void bfs(int i){
	memset (vst, 0,sizeof(vst));
	
	queue<Node>q;
	ans[i][i][0]=0;
	vst[i][0]=1;
	
	q.push({i,0});
	
	while(!q.empty()){
		Node now=q.front();
		int u=now.u;
		int p=now.p;
		q.pop();
		
		for(int j=0;j<e[u].size();j++)
			if(!vst[e[u][j]][(p&1)^1]){
				int v=e[u][j];
				vst[v][(p&1)^1]=1;
				ans[i][v][(p&1)^1]=p+1;
				q.push({v,p+1});
			}
	}
}

void query(){
	while(q--){
		int a,b,x;
		cin>>a>>b>>x;
		
		cout<<(ans[a][b][x&1]<=x?"YES":"NO")<<"\n";
	}
}

int main(){
	
	memset(ans,0x3f,sizeof(ans));
	
	cin>>n>>m>>q;
	
	for(int i=1;i<=m;i++){
		int u,v;
		cin>>u>>v;
		
		e[u].push_back(v);
		e[v].push_back(u);
	}
	
	for(int i=1;i<=n;i++){
		bfs(i);
	}
	
	query();
	
	return 0;
}

Test 1

Group: 1, 2

Verdict: ACCEPTED

Test 2

Group: 1, 2

Verdict: ACCEPTED

Test 3

Group: 2

Verdict: ACCEPTED

Test 4

Group: 1, 2

Verdict: ACCEPTED

Test 5

Group: 1, 2

Verdict: ACCEPTED

Test 6

Group: 2

Verdict: ACCEPTED

Test 7

Group: 2

Verdict: ACCEPTED

Test 8

Group: 1, 2

Verdict: ACCEPTED

Test 9

Group: 2

Verdict: ACCEPTED

Test 10

Group: 2

Verdict: ACCEPTED