Submission #382219

#	Time	Username	Problem	Language	Result	Execution time	Memory
382219		vishesh312	Star triangles (IZhO11_triangle)	C++17	100 / 100	457 ms	9196 KiB

triangle

#include "bits/stdc++.h"
using namespace std;
/*
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
using ordered_set = tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update>;
*/

#define all(x) begin(x), end(x)
#define sz(x) (int)x.size()

using ll = long long;
const int mod = 1e9+7;

void solve(int tc) {
    int n;
    cin >> n;
    vector<pair<ll, ll>> v(n);
    map<ll, ll> cnta, cntb;
    for (auto &[a, b] : v) {
        cin >> a >> b;
        ++cnta[a], ++cntb[b];
    }
    ll ans = 0;
    for (auto &[a, b] : v) {
        ans += (cnta[a]-1) * (cntb[b]-1);
    }
    cout << ans << '\n';
}

signed main() {
    ios_base::sync_with_stdio(false); cin.tie(NULL);
    int tc = 1;
    //cin >> tc;
    for (int i = 1; i <= tc; ++i) solve(i);
    return 0;
}

• Subtask 1: 100 / 100