Submission #86997

#	Time	Username	Problem	Language	Result	Execution time	Memory
86997		rakuten	Star triangles (IZhO11_triangle)	C++14	100 / 100	815 ms	9468 KiB

triangle

#include <bits/stdc++.h>

#define fr first
#define sc second
#define pb push_back
#define mk make_pair
#define int long long
#define OK puts("OK")
#define sz(s) (int)s.size()
#define all(s) s.begin(), s.end()

using namespace std;

const int N = 3e5+10;
const int inf = 1e9+7;
int n , l ,r;
pair < int,int > a[N];
int ans = 0;
map < int , int > x  , y ;

 main(){

	cin >> n;
	for(int i = 1 ; i <= n ; i++ )
    {
		cin >> a[i].fr >> a[i].sc;
		x[a[i].fr] ++ ;
		y[a[i].sc] ++ ;
	}

	for(int i = 1 ; i <= n ; i++ )
    {
		l = x[a[i].fr] -1 ;
		r = y[a[i].sc] -1 ;
		ans += l*r ;
	}

	cout << ans << endl;
}

Compilation message (stderr)

triangle.cpp:21:7: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
  main(){
       ^

• Subtask 1: 100 / 100