Submission #521900

#	Time	Username	Problem	Language	Result	Execution time	Memory
521900		Ronin13	Star triangles (IZhO11_triangle)	C++14	100 / 100	305 ms	13340 KiB

triangle

#include<bits/stdc++.h>
#define ll long long
#define ull unsigned ll
#define pb push_back
#define epb emplace_back
#define f first
#define s second
#define pii pair<int,int>
#define pll pair<ll,ll>
#define inf 1e9+1
#define linf 1e18+1
using namespace std;
int dp[100001][101];
map<ll,ll>usedx,usedy;
int main(){
    ios_base::sync_with_stdio(false);cin.tie(0);
    int n;cin>>n;
    int x[n+1],y[n+1];
    for(int i=1;i<=n;i++)cin>>x[i]>>y[i];
    for(int i=1;i<=n;i++){
        usedx[x[i]]++;
        usedy[y[i]]++;
    }
    ll ans=0;
    for(int i=1;i<=n;i++){
        ans+=(usedx[x[i]]-1)*(usedy[y[i]]-1);
    }
    cout<<ans;
    return 0;
}

• Subtask 1: 100 / 100