Submission #798213

#	Time	Username	Problem	Language	Result	Execution time	Memory
798213		alittlemiddle	Star triangles (IZhO11_triangle)	C++14	0 / 100	1 ms	1876 KiB

triangle

#include <bits/stdc++.h>
#define el '\n'
#define fi first
#define sc second
#define int ll
#define pii pair<int, int>
#define all(v) v.begin(), v.end()
using namespace std;
using ll=long long;
using ull=unsigned long long;
using ld=long double;
const int mod=1e9+7;
const int N=1e5+11;
int mp1[N],mp2[N], n, x[N],y[N], ans;
void sol()
{
    memset(mp1, -1, sizeof mp1);
    memset(mp2, -1, sizeof mp2);
    cin >> n;
    for(int i=1;i<=n; i++)
    {
        cin >> x[i] >> y[i];
        mp1[x[i]]++;
        mp2[y[i]]++;
    }
    for(int i=1; i<=n; i++) ans+=mp1[x[i]]*mp2[y[i]];
    cout << ans;
}
signed main()
{
//    freopen("divisor.INP", "r", stdin);
//    freopen("divisor.OUT", "w", stdout);
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    int t=1;
    //cin >> t;
    while(t--)
    {
        sol();
    }
}

• Subtask 1: 0 / 100