#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;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
212 KB |
Output is correct |
2 |
Incorrect |
1 ms |
320 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
1 ms |
212 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
266 ms |
24780 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
212 KB |
Output is correct |
2 |
Incorrect |
1 ms |
320 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |