제출 #739347

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
739347		Unforgettablepl	Star triangles (IZhO11_triangle)	C++17	100 / 100	100 ms	14156 KiB

triangle

/*
ID: samikgo1
TASK:
LANG: C++
*/
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<ll,ll> pll;
#define all(x) x.begin(),x.end()
#define allr(x) x.rbegin(),x.rend()
#define f first
#define s second
//#define x first
//#define y second
const int INF = INT32_MAX;

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
//    freopen("measurement.in","r",stdin);
//    freopen("measurement.out","w",stdout);
    ll n;
    cin >> n;
    vector<pll> points(n);
    for(pll&i:points)cin>>i.f>>i.s;
    unordered_map<ll,ll> x_axis;
    unordered_map<ll,ll> y_axis;
    ll ans = 0;
    for (pll &i: points) {
        x_axis[i.first]++;
        y_axis[i.second]++;
    }
    for (pll &i: points) {
        ans+=(x_axis[i.first]-1)*(y_axis[i.second]-1);
    }
    cout << ans;
}

• Subtask 1: 100 / 100