#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
#define fi first
#define se second
#define pb push_back
#define TC int t; cin>>t; while(t--)
#define all(x) (x).begin(),(x).end()
//*AC BERSAMA ALLAH FORTIS FORTUNA ADIUVAT
const ll nx = 1e5+5;
vector<ll> adj[nx];
bool on[nx], vis[nx];
ll dp[nx][2][2];
ll n;
void dfs(ll nd){
vis[nd] = 1;
if(on[nd])
dp[nd][1][0] = 1, dp[nd][0][1] = 0;
else
dp[nd][1][1] = 1, dp[nd][0][0] = 0;
for(ll i : adj[nd]){
if(!vis[i]){
dfs(i);
ll x = dp[nd][0][0], y = dp[nd][0][1];
dp[nd][0][0] = min(x + dp[i][0][0], y + dp[i][1][0]);
dp[nd][0][1] = min(y + dp[i][0][0], x + dp[i][1][0]);
x = dp[nd][1][0], y = dp[nd][1][1];
dp[nd][1][0] = min(x + dp[i][0][1], y + dp[i][1][1]);
dp[nd][1][1] = min(y + dp[i][0][1], x + dp[i][1][1]);
}
}
}
int main() {
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
cin >> n;
for(ll i=1; i<n; i++){
ll u, v;
cin >> u >> v;
adj[u].push_back(v);
adj[v].push_back(u);
}
for(ll i=1; i<=n; i++){
cin >> on[i];
}
for(ll i=1; i<=n; i++){
for(ll j=0; j<=1; j++)
dp[i][j][0] = dp[i][j][1] = 1e6;
}
dfs(1);
if(min(dp[1][1][0], dp[1][0][0]) > n){
cout << "impossible\n";
}
else cout << min(dp[1][1][0], dp[1][0][0]) << '\n';
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
3676 KB |
Output is correct |
2 |
Correct |
1 ms |
3676 KB |
Output is correct |
3 |
Correct |
1 ms |
3676 KB |
Output is correct |
4 |
Correct |
1 ms |
3676 KB |
Output is correct |
5 |
Correct |
1 ms |
3676 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
3676 KB |
Output is correct |
2 |
Correct |
1 ms |
3676 KB |
Output is correct |
3 |
Correct |
1 ms |
3676 KB |
Output is correct |
4 |
Correct |
1 ms |
3676 KB |
Output is correct |
5 |
Correct |
1 ms |
3676 KB |
Output is correct |
6 |
Correct |
1 ms |
3676 KB |
Output is correct |
7 |
Correct |
1 ms |
3672 KB |
Output is correct |
8 |
Correct |
1 ms |
3676 KB |
Output is correct |
9 |
Correct |
1 ms |
3672 KB |
Output is correct |
10 |
Correct |
1 ms |
3676 KB |
Output is correct |
11 |
Correct |
1 ms |
3672 KB |
Output is correct |
12 |
Correct |
1 ms |
3676 KB |
Output is correct |
13 |
Correct |
1 ms |
3676 KB |
Output is correct |
14 |
Correct |
1 ms |
3676 KB |
Output is correct |
15 |
Correct |
1 ms |
3676 KB |
Output is correct |
16 |
Correct |
1 ms |
3676 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
31 ms |
15448 KB |
Output is correct |
2 |
Correct |
32 ms |
15196 KB |
Output is correct |
3 |
Correct |
34 ms |
15720 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
32 ms |
15392 KB |
Output is correct |
2 |
Correct |
42 ms |
15232 KB |
Output is correct |
3 |
Correct |
38 ms |
15468 KB |
Output is correct |
4 |
Correct |
28 ms |
9524 KB |
Output is correct |
5 |
Correct |
34 ms |
9808 KB |
Output is correct |
6 |
Correct |
36 ms |
10064 KB |
Output is correct |
7 |
Correct |
1 ms |
3932 KB |
Output is correct |
8 |
Correct |
11 ms |
7324 KB |
Output is correct |
9 |
Correct |
35 ms |
9560 KB |
Output is correct |
10 |
Correct |
41 ms |
9812 KB |
Output is correct |
11 |
Correct |
37 ms |
10144 KB |
Output is correct |
12 |
Correct |
32 ms |
10064 KB |
Output is correct |
13 |
Correct |
30 ms |
10272 KB |
Output is correct |
14 |
Correct |
32 ms |
10324 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
3676 KB |
Output is correct |
2 |
Correct |
1 ms |
3676 KB |
Output is correct |
3 |
Correct |
1 ms |
3676 KB |
Output is correct |
4 |
Correct |
1 ms |
3676 KB |
Output is correct |
5 |
Correct |
1 ms |
3676 KB |
Output is correct |
6 |
Correct |
1 ms |
3676 KB |
Output is correct |
7 |
Correct |
1 ms |
3672 KB |
Output is correct |
8 |
Correct |
1 ms |
3676 KB |
Output is correct |
9 |
Correct |
1 ms |
3672 KB |
Output is correct |
10 |
Correct |
1 ms |
3676 KB |
Output is correct |
11 |
Correct |
1 ms |
3672 KB |
Output is correct |
12 |
Correct |
1 ms |
3676 KB |
Output is correct |
13 |
Correct |
1 ms |
3676 KB |
Output is correct |
14 |
Correct |
1 ms |
3676 KB |
Output is correct |
15 |
Correct |
1 ms |
3676 KB |
Output is correct |
16 |
Correct |
1 ms |
3676 KB |
Output is correct |
17 |
Correct |
31 ms |
15448 KB |
Output is correct |
18 |
Correct |
32 ms |
15196 KB |
Output is correct |
19 |
Correct |
34 ms |
15720 KB |
Output is correct |
20 |
Correct |
32 ms |
15392 KB |
Output is correct |
21 |
Correct |
42 ms |
15232 KB |
Output is correct |
22 |
Correct |
38 ms |
15468 KB |
Output is correct |
23 |
Correct |
28 ms |
9524 KB |
Output is correct |
24 |
Correct |
34 ms |
9808 KB |
Output is correct |
25 |
Correct |
36 ms |
10064 KB |
Output is correct |
26 |
Correct |
1 ms |
3932 KB |
Output is correct |
27 |
Correct |
11 ms |
7324 KB |
Output is correct |
28 |
Correct |
35 ms |
9560 KB |
Output is correct |
29 |
Correct |
41 ms |
9812 KB |
Output is correct |
30 |
Correct |
37 ms |
10144 KB |
Output is correct |
31 |
Correct |
32 ms |
10064 KB |
Output is correct |
32 |
Correct |
30 ms |
10272 KB |
Output is correct |
33 |
Correct |
32 ms |
10324 KB |
Output is correct |
34 |
Correct |
1 ms |
3672 KB |
Output is correct |
35 |
Correct |
1 ms |
3676 KB |
Output is correct |
36 |
Correct |
1 ms |
3676 KB |
Output is correct |
37 |
Correct |
2 ms |
3676 KB |
Output is correct |
38 |
Correct |
1 ms |
3676 KB |
Output is correct |
39 |
Correct |
1 ms |
3676 KB |
Output is correct |
40 |
Correct |
1 ms |
3676 KB |
Output is correct |
41 |
Correct |
1 ms |
3676 KB |
Output is correct |
42 |
Correct |
1 ms |
3676 KB |
Output is correct |
43 |
Correct |
2 ms |
3672 KB |
Output is correct |
44 |
Correct |
1 ms |
3848 KB |
Output is correct |
45 |
Correct |
40 ms |
15240 KB |
Output is correct |
46 |
Correct |
34 ms |
15164 KB |
Output is correct |
47 |
Correct |
33 ms |
15452 KB |
Output is correct |
48 |
Correct |
29 ms |
9524 KB |
Output is correct |
49 |
Correct |
36 ms |
10024 KB |
Output is correct |
50 |
Correct |
33 ms |
10064 KB |
Output is correct |
51 |
Correct |
2 ms |
3932 KB |
Output is correct |
52 |
Correct |
11 ms |
7384 KB |
Output is correct |
53 |
Correct |
32 ms |
9564 KB |
Output is correct |
54 |
Correct |
33 ms |
9820 KB |
Output is correct |
55 |
Correct |
31 ms |
10096 KB |
Output is correct |
56 |
Correct |
32 ms |
10076 KB |
Output is correct |
57 |
Correct |
36 ms |
10064 KB |
Output is correct |
58 |
Correct |
35 ms |
10332 KB |
Output is correct |
59 |
Correct |
11 ms |
7256 KB |
Output is correct |
60 |
Correct |
28 ms |
9308 KB |
Output is correct |
61 |
Correct |
31 ms |
9564 KB |
Output is correct |
62 |
Correct |
32 ms |
9812 KB |
Output is correct |
63 |
Correct |
36 ms |
9576 KB |
Output is correct |
64 |
Correct |
31 ms |
9820 KB |
Output is correct |
65 |
Correct |
31 ms |
10200 KB |
Output is correct |
66 |
Correct |
41 ms |
10400 KB |
Output is correct |
67 |
Correct |
25 ms |
9868 KB |
Output is correct |
68 |
Correct |
24 ms |
9932 KB |
Output is correct |
69 |
Correct |
27 ms |
9936 KB |
Output is correct |
70 |
Correct |
25 ms |
9936 KB |
Output is correct |