Submission #679984

#	Time	Username	Problem	Language	Result	Execution time	Memory
679984		Karuk	Star triangles (IZhO11_triangle)	C++14	100 / 100	537 ms	38920 KiB

triangle

#include<bits/stdc++.h>
using namespace std;
    vector<int>x[600001];
    vector<int>y[600001];
int main() {
    int n;
    cin>>n;
    set<int>s;
    pair<int,int>a[n];
    for(int i=0;i<n;i++) {
        int x,y;cin>>x>>y;
        a[i]={x,y};
        s.insert(x);
        s.insert(y);
    }
    vector<int>v;
    for(int i:s)v.push_back(i);
    map<int,int>m;
    for(int i=0;i<v.size();i++) {
        m[v[i]]=i;
    }
    for(int i=0;i<n;i++) {
        a[i].first=m[a[i].first];
        a[i].second=m[a[i].second];
        x[a[i].first].push_back(a[i].second);
        y[a[i].second].push_back(a[i].first);
    }
    long long ans=0;
    for(int i=0;i<n;i++) {
        ans+=(x[a[i].first].size()-1)*(y[a[i].second].size()-1);
    }
    cout<<ans<<endl;
    return 0;
}
/**
3
0 0
1 0
0 1
*/

Compilation message (stderr)

triangle.cpp: In function 'int main()':
triangle.cpp:19:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   19 |     for(int i=0;i<v.size();i++) {
      |                 ~^~~~~~~~~

• Subtask 1: 100 / 100