Submission #379680

#	Time	Username	Problem	Language	Result	Execution time	Memory
379680		SolarSystem	Star triangles (IZhO11_triangle)	C++17	100 / 100	502 ms	18156 KiB

triangle

#include <iostream>
#include <vector>
#include <algorithm>
#include <iterator>
#include <string>
#include <math.h>
#include <set>
#include <map>
#include <queue>
#include <stack>
#include <stdio.h>
#include <numeric>
#include <iomanip>
#include <random>

using namespace std;

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);

    int n;
    cin >> n;

    vector<pair<long long, long long>> pts(n);

    for (int i = 0; i < n; i++) {
        cin >> pts[i].first >> pts[i].second;
    }

    map<long long, long long> mpx;
    map<long long, vector<long long>> mpy;

    for (int i = 0; i < n; i++) {
        mpx[pts[i].first]++;
        mpy[pts[i].second].push_back(pts[i].first);
    }

    long long ans = 0;

    for (auto e: mpy) {
        long long curr = 0;

        for (auto u: e.second) {
            curr += mpx[u] - 1;
        }

        curr *= ((int) e.second.size() - 1);

        ans += curr;
    }

    cout << ans << endl;

    return 0;
}

• Subtask 1: 100 / 100