Peli

#include <iostream>
#include <vector>
#include <set>
using namespace std;
using ll = int64_t;
const int N = 2500;

int n, m, q;
vector<int> V[N];
int D[N][N][2];
set<pair<int,int>> Q;

int main() {
  cin >> n >> m >> q;
  for (int i=0; i < m; ++i) {
    int a, b;
    cin >> a >> b;
    V[a-1].push_back(b-1);
    V[b-1].push_back(a-1);
  }
  for (int i=0; i < n; ++i) {
    for (int j=0; j < n; ++j) D[i][j][0] = D[i][j][1] = 2e9;
  }
  for (int i=0; i < n; ++i) {
    Q.insert({0,i});
    D[i][i][0] = 0;
    while (Q.size()) {
      auto [s,j] = *Q.begin();
      Q.erase(Q.begin());
      ++s;
      for (int k : V[j]) {
        if (s < D[i][k][s&1]) {
          D[i][k][s&1] = s;
          Q.insert({s,k});
        }
      }
    }
  }
  for (int i=0; i < q; ++i) {
    int a, b, x;
    cin >> a >> b >> x;
    if (D[a-1][b-1][x&1] <= x) {
      cout << "YES\n";
    } else {
      cout << "NO\n";
    }
  }
}

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