Submission #879931

#	Time	Username	Problem	Language	Result	Execution time	Memory
879931		heeheeheehaaw	Star triangles (IZhO11_triangle)	C++17	100 / 100	420 ms	10172 KiB

triangle

#include <bits/stdc++.h>
#define int long long

using namespace std;

map<int, vector<int>> aux;
vector<int> v;
map<int, int> fr;

signed main()
{
    int n;
    cin>>n;
    for(int i = 1; i <= n; i++)
    {
        int x, y;
        cin>>x>>y;
        aux[x].push_back(y);
        fr[y]++;
    }

    int rez = 0;
    for(auto i : aux)
    {
        v = i.second;
        sort(v.begin(), v.end());
        int cnt = -1;
        for(int j = 0; j < v.size(); j++)
        {
            cnt++;
            rez += cnt * (fr[v[j]] - 1);
        }
        cnt = -1;
        for(int j = (int)v.size() - 1; j >= 0; j--)
        {
            cnt++;
            rez += cnt * (fr[v[j]] - 1);
        }
    }

    cout<<rez;
    return 0;
}

Compilation message (stderr)

triangle.cpp: In function 'int main()':
triangle.cpp:28:26: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   28 |         for(int j = 0; j < v.size(); j++)
      |                        ~~^~~~~~~~~~

• Subtask 1: 100 / 100