Submission #5394

#	Time	Username	Problem	Language	Result	Execution time	Memory
5394		baneling100	Star triangles (IZhO11_triangle)	C++98	100 / 100	500 ms	6588 KiB

triangle

#include <stdio.h>
#include <map>

using namespace std;

map <int,int> m1;
map <int,int> m2;
int n, x[300001], y[300001];
long long ans;

void input(void)
{
    int i;

    scanf("%d",&n);
    for(i=1 ; i<=n ; i++)
    {
        scanf("%d %d",&x[i],&y[i]);
        m1[x[i]]++;
        m2[y[i]]++;
    }
}

void process(void)
{
    int i;

    for(i=1 ; i<=n ; i++)
        ans+=((long long)m1[x[i]]-1)*(m2[y[i]]-1);
}

void output(void)
{
    printf("%lld",ans);
}

int main(void)
{
    input();
    process();
    output();

    return 0;
}

• Subtask 1: 100 / 100