Peli

#include<bits/stdc++.h>
using namespace std;
#define forn(i,n) for(int i=0;i<n;++i)
#define N 2505
#define M 5005
#define inf 1.01e9
typedef pair<int,int> pii;

int n,m,q,a[N][N][2],z[N][2];
vector<int> v[N];

void haku(int S) {
    memset(z,0,sizeof(z));
    queue<pii> q;
    a[S][S][0] = 0;
    q.push({0, S});
    while(!q.empty()) {
        auto[e, s] = q.front();
        q.pop();
        e++;
        for (auto i : v[s]) if (!z[i][e&1]) {
            if (a[S][i][e&1] < e)
                continue;
            a[S][i][e&1] = e;
            q.push({e, i});
        }
    }
}

int main() {
    cin.tie(0)->sync_with_stdio(false);
    cout.tie(0);
    cin>>n>>m>>q;
    memset(a, 63, sizeof(a));
    int ina,inb,x;
    forn(i,m) {
        cin>>ina>>inb;
        v[ina].push_back(inb);
        v[inb].push_back(ina);
    }
    forn(i,n) haku(i+1); 
    forn(i,q) { 
        cin>>ina>>inb>>x;
        if (a[ina][inb][x&1]<=x)
            cout<<"YES"<<endl;
        else cout<<"NO"<<endl;
    }
}

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: TIME LIMIT EXCEEDED

Test 10

Group: 2

Verdict: TIME LIMIT EXCEEDED