Submission #445846

#	Time	Username	Problem	Language	Result	Execution time	Memory
445846		simon2712	Star triangles (IZhO11_triangle)	C++14	0 / 100	5 ms	460 KiB

triangle

#include <bits/stdc++.h>
using namespace std;
ifstream fin("triangles.in");
ofstream fout("triangles.out");
pair<int,int> v[3000001];
int main()
{
    int n,i,st,dr,mij,st2,dr2,st3,dr3;
    unsigned long long rez=0;
    fin>>n;
    for(i=1;i<=n;i++)
        fin>>v[i].first>>v[i].second;
    sort(v+1,v+n+1);
    for(i=1;i<=n;i++)
    {
        st=1;
        dr=n;
        while(st<=dr)
        {
            mij=(st+dr)/2;
            if(v[mij].first<=v[i].first)
                st=mij+1;
            else
                dr=mij-1;
        }
        st2=st-1;
        st=1;
        dr=n;
        while(st<=dr)
        {
            mij=(st+dr)/2;
            if(v[mij].first>=v[i].first)
                dr=mij-1;
            else
                st=mij+1;
        }
        dr2=dr+1;
        st=1;
        dr=n;
        while(st<=dr)
        {
            mij=(st+dr)/2;
            if(v[mij].second>=v[i].second)
                dr=mij-1;
            else
                st=mij+1;
        }
        dr3=dr+1;
        st=1;
        dr=n;
        while(st<=dr)
        {
            mij=(st+dr)/2;
            if(v[mij].second<=v[i].second)
                st=mij+1;
            else
                dr=mij-1;
        }
        st3=st-1;
        rez+=(dr3-st3)*(dr2-st2);
    }
    fout<<rez;
    return 0;
}

• Subtask 1: 0 / 100