Submission #731027

#	Time	Username	Problem	Language	Result	Execution time	Memory
731027		Karpin	Love Polygon (BOI18_polygon)	C++17	0 / 100	266 ms	24780 KiB

polygon

#include <bits/stdc++.h>

using namespace std;


#define ll long long
#define vt vector
#define ar array


void solve(){

    int n;
    cin >> n;

    if (n % 2 == 1){
        cout << -1 << endl;
        return;
    }

    map<string, string> loving;
    map<string, vt<string>> isLoved;

    for(int i = 0; i < n; i++){
        string a, b;
        cin >> a >> b;
        loving[a] = b;
        if (isLoved.find(b) == isLoved.end()) isLoved[b] = {};
        isLoved[b].push_back(a);
    }

    cout << n / 2 << endl;






		

}

int main(){

	ios::sync_with_stdio(0);
	cin.tie(0);
	
	int testcases = 1;

	// cin >> testcases;

	while(testcases--){
		solve();
	}

	return 0;

}

• Subtask 1: 0 / 21
• Subtask 2: 0 / 25
• Subtask 3: 0 / 29
• Subtask 4: 0 / 25