Submission #545019

#	Time	Username	Problem	Language	Result	Execution time	Memory
545019		MilosMilutinovic	Star triangles (IZhO11_triangle)	C++14	100 / 100	269 ms	12168 KiB

triangle

#include<bits/stdc++.h>

#define fi first
#define se second
#define pb push_back
#define mp make_pair

using namespace std;

typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;

template<typename T> bool chkmin(T&x,T y){return x>y?x=y,1:0;}
template<typename T> bool chkmax(T&x,T y){return x<y?x=y,1:0;}

int readint(){
	int x=0,f=1; char ch=getchar();
	while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();}
	while(ch>='0'&&ch<='9'){x=x*10+ch-'0';ch=getchar();}
	return x*f;
}

int n,x[300005],y[300005];
map<int,int> cx,cy;

int main(){
	n=readint();
	for(int i=1;i<=n;i++)x[i]=readint(),y[i]=readint(),cx[x[i]]++,cy[y[i]]++;
	ll ans=0;
	for(int i=1;i<=n;i++)ans+=(cx[x[i]]-1)*1LL*(cy[y[i]]-1);
	printf("%lld\n",ans);
	return 0;
}

• Subtask 1: 100 / 100