oj.uz

Submission #838974

# Submission time Handle Problem Language Result Execution time Memory
838974 2023-08-28T11:35:02 Z winter0101 The Xana coup (BOI21_xanadu) C++14
100 / 100
 44 ms 17020 KB 
#include<bits/stdc++.h>
using namespace std;
#define all(fl) fl.begin(),fl.end()
#define pb push_back
#define fi first
#define se second
#define for1(i,j,k) for(int i=j;i<=k;i++)
#define for2(i,j,k) for(int i=j;i>=k;i--)
#define for3(i,j,k,l) for(int i=j;i<=k;i+=l)
#define lb lower_bound
#define ub upper_bound
#define sz(a) (int)a.size()
#define pii pair<int,int>
#define pli pair<long long,int>
#define gcd __gcd
#define lcm(x,y) x*y/__gcd(x,y)
const int maxn=1e5+9;
int f[maxn][2][2];
vector<int>a[maxn];
int b[maxn];
int n;
void dfs(int u,int par){
//f[i][j][k] j use i switch or not ?
for1(i,0,1){
for1(j,0,1){
f[u][i][j]=n+1;
}
}
f[u][0][b[u]]=0;
f[u][1][1^b[u]]=1;
for(auto v:a[u]){
    if (v==par)continue;
    dfs(v,u);
    //if use
    int v1=f[u][1][1],v0=f[u][1][0];
    f[u][1][0]=min(v1+f[v][1][1],v0+f[v][0][1]);
    f[u][1][1]=min(v1+f[v][0][1],v0+f[v][1][1]);
    //if not use
    v1=f[u][0][1],v0=f[u][0][0];
    f[u][0][0]=min(v1+f[v][1][0],v0+f[v][0][0]);
    f[u][0][1]=min(v1+f[v][0][0],v0+f[v][1][0]);
    //cout<<v<<" "<<f[u][0][1]<<" "<<f[u][0][0]<<'\n';
}
}
signed main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    //freopen("temp.INP","r",stdin);
    //freopen("temp.OUT","w",stdout);
    cin>>n;
    for1(i,1,n-1){
    int u,v;
    cin>>u>>v;
    a[u].pb(v);
    a[v].pb(u);
    }
    for1(i,1,n)cin>>b[i];
    dfs(1,0);
    int ans=min(f[1][1][0],f[1][0][0]);
    if (ans>=n+1)cout<<"impossible";
    else cout<<ans;

}

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 2768 KB Output is correct
2 Correct 2 ms 2644 KB Output is correct
3 Correct 1 ms 2644 KB Output is correct
4 Correct 1 ms 2644 KB Output is correct
5 Correct 1 ms 2644 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 2768 KB Output is correct
2 Correct 2 ms 2644 KB Output is correct
3 Correct 1 ms 2644 KB Output is correct
4 Correct 1 ms 2644 KB Output is correct
5 Correct 1 ms 2644 KB Output is correct
6 Correct 2 ms 2644 KB Output is correct
7 Correct 1 ms 2644 KB Output is correct
8 Correct 1 ms 2644 KB Output is correct
9 Correct 1 ms 2644 KB Output is correct
10 Correct 1 ms 2644 KB Output is correct
11 Correct 2 ms 2644 KB Output is correct
12 Correct 1 ms 2644 KB Output is correct
13 Correct 1 ms 2644 KB Output is correct
14 Correct 1 ms 2644 KB Output is correct
15 Correct 2 ms 2644 KB Output is correct
16 Correct 1 ms 2644 KB Output is correct

Subtask #3
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 32 ms 16844 KB Output is correct
2 Correct 32 ms 16660 KB Output is correct
3 Correct 40 ms 16900 KB Output is correct

Subtask #4
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 37 ms 16844 KB Output is correct
2 Correct 33 ms 16680 KB Output is correct
3 Correct 33 ms 17020 KB Output is correct
4 Correct 28 ms 8396 KB Output is correct
5 Correct 31 ms 8916 KB Output is correct
6 Correct 33 ms 9036 KB Output is correct
7 Correct 2 ms 2644 KB Output is correct
8 Correct 13 ms 4820 KB Output is correct
9 Correct 30 ms 9044 KB Output is correct
10 Correct 32 ms 9172 KB Output is correct
11 Correct 36 ms 9516 KB Output is correct
12 Correct 32 ms 9812 KB Output is correct
13 Correct 32 ms 8652 KB Output is correct
14 Correct 31 ms 9100 KB Output is correct

Subtask #5
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 2768 KB Output is correct
2 Correct 2 ms 2644 KB Output is correct
3 Correct 1 ms 2644 KB Output is correct
4 Correct 1 ms 2644 KB Output is correct
5 Correct 1 ms 2644 KB Output is correct
6 Correct 2 ms 2644 KB Output is correct
7 Correct 1 ms 2644 KB Output is correct
8 Correct 1 ms 2644 KB Output is correct
9 Correct 1 ms 2644 KB Output is correct
10 Correct 1 ms 2644 KB Output is correct
11 Correct 2 ms 2644 KB Output is correct
12 Correct 1 ms 2644 KB Output is correct
13 Correct 1 ms 2644 KB Output is correct
14 Correct 1 ms 2644 KB Output is correct
15 Correct 2 ms 2644 KB Output is correct
16 Correct 1 ms 2644 KB Output is correct
17 Correct 32 ms 16844 KB Output is correct
18 Correct 32 ms 16660 KB Output is correct
19 Correct 40 ms 16900 KB Output is correct
20 Correct 37 ms 16844 KB Output is correct
21 Correct 33 ms 16680 KB Output is correct
22 Correct 33 ms 17020 KB Output is correct
23 Correct 28 ms 8396 KB Output is correct
24 Correct 31 ms 8916 KB Output is correct
25 Correct 33 ms 9036 KB Output is correct
26 Correct 2 ms 2644 KB Output is correct
27 Correct 13 ms 4820 KB Output is correct
28 Correct 30 ms 9044 KB Output is correct
29 Correct 32 ms 9172 KB Output is correct
30 Correct 36 ms 9516 KB Output is correct
31 Correct 32 ms 9812 KB Output is correct
32 Correct 32 ms 8652 KB Output is correct
33 Correct 31 ms 9100 KB Output is correct
34 Correct 2 ms 2644 KB Output is correct
35 Correct 2 ms 2644 KB Output is correct
36 Correct 2 ms 2692 KB Output is correct
37 Correct 2 ms 2644 KB Output is correct
38 Correct 2 ms 2644 KB Output is correct
39 Correct 2 ms 2644 KB Output is correct
40 Correct 1 ms 2644 KB Output is correct
41 Correct 1 ms 2644 KB Output is correct
42 Correct 2 ms 2644 KB Output is correct
43 Correct 2 ms 2644 KB Output is correct
44 Correct 2 ms 2644 KB Output is correct
45 Correct 32 ms 16844 KB Output is correct
46 Correct 31 ms 16596 KB Output is correct
47 Correct 33 ms 16844 KB Output is correct
48 Correct 40 ms 8524 KB Output is correct
49 Correct 32 ms 8868 KB Output is correct
50 Correct 32 ms 9044 KB Output is correct
51 Correct 1 ms 2644 KB Output is correct
52 Correct 12 ms 4820 KB Output is correct
53 Correct 30 ms 9044 KB Output is correct
54 Correct 32 ms 9168 KB Output is correct
55 Correct 35 ms 9548 KB Output is correct
56 Correct 31 ms 9804 KB Output is correct
57 Correct 29 ms 8604 KB Output is correct
58 Correct 34 ms 9056 KB Output is correct
59 Correct 11 ms 4820 KB Output is correct
60 Correct 29 ms 8396 KB Output is correct
61 Correct 32 ms 9036 KB Output is correct
62 Correct 33 ms 9164 KB Output is correct
63 Correct 44 ms 9148 KB Output is correct
64 Correct 34 ms 9164 KB Output is correct
65 Correct 29 ms 9548 KB Output is correct
66 Correct 28 ms 9548 KB Output is correct
67 Correct 26 ms 9420 KB Output is correct
68 Correct 31 ms 9412 KB Output is correct
69 Correct 24 ms 9412 KB Output is correct
70 Correct 25 ms 9420 KB Output is correct