Submission #89880

#	Time	Username	Problem	Language	Result	Execution time	Memory
89880		popovicirobert	Star triangles (IZhO11_triangle)	C++14	100 / 100	492 ms	20028 KiB

triangle

#include <bits/stdc++.h>
#define lsb(x) (x & (-x))
#define ll long long
#define ull unsigned long long
#define ld long double
// 217
// 44

using namespace std;

const int MAXN = (int) 3e5;

pair <int, int> pts[MAXN + 1];

map <int, int> frx, fry;

int main() {
    //ifstream cin("A.in");
    //ofstream cout("A.out");
    int i, n;
    ios::sync_with_stdio(false);
    cin.tie(0), cout.tie(0);
    cin >> n;
    for(i = 1; i <= n; i++) {
        int x, y;
        cin >> x >> y;
        pts[i] = {x, y};
        frx[x]++;
        fry[y]++;
        //fr[{x, y}]++;
    }
    ll ans = 0;
    for(i = 1; i <= n; i++) {
        ans += 1LL * (frx[pts[i].first] - 1) * (fry[pts[i].second] - 1);
    }
    cout << ans;
    //cin.close();
    //cout.close();
    return 0;
}

• Subtask 1: 100 / 100