//Bismi Allah
#include "bits/stdc++.h"
using namespace std;
signed main () {
ios::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
int n;
cin >> n;
map <string,int> mp;
vector <int> used(n, 0), dp(n, 0), g[n], unite(n, 0), loved(n, 0), rk(n, 0);
function <void(int,int)> dfs=[&](int v, int p) {
used[v] = 1;
rk[v] = 1;
for(auto u : g[v]) {
if(used[u]) continue;
dfs(u, v);
rk[v] += rk[u];
}
if(unite[v]) return;
if(p != -1 && unite[p] == 0) {
unite[p] = 1;
unite[v] = 1;
}
};
for(int i = 0; i < n; i ++) {
string u, v;
cin >> u >> v;
if(mp.count(u) == 0) mp[u] = mp.size();
if(mp.count(v) == 0) mp[v] = mp.size();
loved[mp[v]] ++;
if(mp[u] == mp[v]) continue;
g[mp[u]].push_back(mp[v]);
g[mp[v]].push_back(mp[u]);
}
if(*min_element(loved.begin(), loved.end()) >= 1) {
if(n % 2 == 1) {
// assert(false);
cout << -1;
return 0;
}
int ans = 0, mod = 0;
for(int i = 0; i < n; i ++) {
if(used[i]) continue;
dfs(i, -1);
if(rk[i] == 2) continue;
ans += rk[i] / 2;
mod += (rk[i] % 2);
}
if(mod % 2 == 1) cout << -1;
else cout << ans + mod;
return 0;
}
if(n % 2 == 1) {
// assert(false);
cout << -1;
return 0;
}
int ans = 0, mod = 0;
for(int i = 0; i < n; i ++) {
if(used[i]) continue;
dfs(i, -1);
}
for(auto i : unite) {
ans += (i == 1);
mod += (i == 0);
}
cout << ans/2+mod;
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
0 ms |
600 KB |
Output is correct |
4 |
Correct |
0 ms |
344 KB |
Output is correct |
5 |
Correct |
0 ms |
348 KB |
Output is correct |
6 |
Correct |
0 ms |
348 KB |
Output is correct |
7 |
Correct |
0 ms |
348 KB |
Output is correct |
8 |
Incorrect |
0 ms |
348 KB |
Output isn't correct |
9 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
348 KB |
Output is correct |
2 |
Correct |
1 ms |
348 KB |
Output is correct |
3 |
Correct |
0 ms |
344 KB |
Output is correct |
4 |
Correct |
268 ms |
23636 KB |
Output is correct |
5 |
Correct |
277 ms |
15440 KB |
Output is correct |
6 |
Correct |
275 ms |
25036 KB |
Output is correct |
7 |
Correct |
264 ms |
15668 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
276 ms |
15700 KB |
Output is correct |
2 |
Correct |
260 ms |
17236 KB |
Output is correct |
3 |
Correct |
135 ms |
12416 KB |
Output is correct |
4 |
Correct |
249 ms |
15700 KB |
Output is correct |
5 |
Correct |
286 ms |
21332 KB |
Output is correct |
6 |
Correct |
252 ms |
15700 KB |
Output is correct |
7 |
Correct |
263 ms |
15720 KB |
Output is correct |
8 |
Correct |
197 ms |
14868 KB |
Output is correct |
9 |
Correct |
270 ms |
15860 KB |
Output is correct |
10 |
Correct |
170 ms |
15884 KB |
Output is correct |
11 |
Correct |
0 ms |
348 KB |
Output is correct |
12 |
Correct |
0 ms |
348 KB |
Output is correct |
13 |
Correct |
0 ms |
348 KB |
Output is correct |
14 |
Correct |
1 ms |
348 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
0 ms |
600 KB |
Output is correct |
4 |
Correct |
0 ms |
344 KB |
Output is correct |
5 |
Correct |
0 ms |
348 KB |
Output is correct |
6 |
Correct |
0 ms |
348 KB |
Output is correct |
7 |
Correct |
0 ms |
348 KB |
Output is correct |
8 |
Incorrect |
0 ms |
348 KB |
Output isn't correct |
9 |
Halted |
0 ms |
0 KB |
- |