Submission #3057932

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Source Code Expand

#include <bits/stdc++.h>

using namespace std;

using int64 = long long;

int main() {
  int N, X[1000], Y[1000];
  map< pair< int, int >, int > mp;
  cin >> N;
  for(int i = 0; i < N; i++) {
    cin >> X[i] >> Y[i];
    mp[{X[i], Y[i]}] = i;
  }
  for(int i = 0; i < N; i++) {
    for(int j = 0; j < N; j++) {
      if(i == j) continue;

      int dx = X[j] - X[i];
      int dy = Y[j] - Y[i];
      if(mp.count({X[i] - dy, Y[i] + dx}) && mp.count({X[j] - dy, Y[j] + dx})) {
        set< int > st{i, j, mp[{X[i] - dy, Y[i] + dx}], mp[{X[j] - dy, Y[j] + dx}]};
        cout << 4 << endl;
        for(auto &p : st) cout << p + 1 << endl;
        return 0;
      }
    }
  }
  cout << 0 << endl;
}

Submission Info

Judge Result