Submission #465909

#	Time	Username	Problem	Language	Result	Execution time	Memory
465909		JasperL	별들과 삼각형 (IZhO11_triangle)	C++14	100 / 100	572 ms	12488 KiB

triangle

#include <iostream>
#include <set>
#include <map>
#include <vector>
using namespace std;

#define maxn 300005

typedef long long ll;

int n, c;
int z[maxn][2];
set<int> s;
map<int,int> mp;
ll ans = 0;

int x[2*maxn], y[2*maxn];

int main() {
    cin >> n;
    for (int i = 0; i < n; i++) {
        cin >> z[i][0] >> z[i][1];
        s.insert(z[i][0]), s.insert(z[i][1]);
    }
    for (int t : s) mp[t] = c++;
    for (int i = 0; i < n; i++) z[i][0] = mp[z[i][0]], z[i][1] = mp[z[i][1]], x[z[i][0]]++, y[z[i][1]]++;
    for (int i = 0; i < n; i++) {
        ans += (ll)(x[z[i][0]] - 1) * (ll)(y[z[i][1]] - 1);
    }
    cout << ans << endl;
}

• Subtask 1: 100 / 100