Submission #90341

#	Time	Username	Problem	Language	Result	Execution time	Memory
90341		Bodo171	Star triangles (IZhO11_triangle)	C++14	100 / 100	967 ms	11716 KiB

triangle

#include <iostream>
#include <map>
#include <algorithm>
#define x first
#define y second
using namespace std;
const int nmax=300005;
map<int,int> X,Y;
pair<int,int> v[nmax];
int n,i;
long long ans;
int main()
{
    cin>>n;
    for(i=1;i<=n;i++)
        cin>>v[i].x>>v[i].y;
    for(int cc=0;cc<4;cc++)
    {
        for(i=1;i<=n;i++)
        {
            if(cc>0)
            {
                v[i].x*=-1;
                if((cc&2)!=((cc-1)&2))
                    v[i].y*=-1;
            }
        }
        sort(v+1,v+n+1);
        for(i=n;i>=1;i--)
       {
        ans+=1LL*X[v[i].x]*Y[v[i].y];
        X[v[i].x]++,Y[v[i].y]++;
       }
       X.clear();Y.clear();
    }
    cout<<ans;
    return 0;
}

• Subtask 1: 100 / 100