oj.uz

Submission #882915

# Submission time Handle Problem Language Result Execution time Memory
882915 2023-12-04T06:36:46 Z dosts The Xana coup (BOI21_xanadu) C++17
100 / 100
 75 ms 25712 KB 
#include <bits/stdc++.h>
using namespace std;
#define sp << " " << 
#define int long long
#define vi vector<int>
#define F(xxx,yyy) for (int xxx=1;xxx<=yyy;xxx++)
#define pii pair<int,int>
const int N = 1e5+1;

vi c(N);
vi edges[N];
int dp[N][2][2];

void dfs(int node,int par,int p,int pp) {
  if (dp[node][p][pp]!=1e9+5) return;
  int tog = c[node]^p^pp;
  dp[node][p][pp] = 1e9;
  int sm = 0;
  vi ones;
  for (auto it : edges[node]) {
    if (it != par) {
      dfs(it,node,0,p);
      dfs(it,node,1,p);
      sm+=dp[it][0][p];
      ones.push_back(dp[it][1][p]-dp[it][0][p]);
    }
  }
  if (!(tog)) dp[node][p][pp] = min(dp[node][p][pp],sm+p);
  if (ones.empty()) return;
  sort(ones.begin(),ones.end());
  for (int i=1;i<(int)ones.size();i++) ones[i]+=ones[i-1];
  int sz = ones.size();
  for (int i=2-tog;i<=sz;i+=2) {
    dp[node][p][pp] = min(dp[node][p][pp],sm+ones[i-1]+p);
  }
}

void solve() {
  int n;
  cin >> n;
  memset(dp,-1,sizeof dp);
  F(i,n-1) {
    int a,b;
    cin >> a >> b;
    edges[a].push_back(b);
    edges[b].push_back(a);
  }
  F(i,n) cin >> c[i];
  F(i,n) {
    for (int j=0;j<2;j++) {
      for (int k=0;k<2;k++) {
        dp[i][j][k] = 1e9+5;
      }
    }
  }
  dfs(1,1,1,0);
  dfs(1,1,0,0); 
  F(i,n) {
    for (int j=0;j<2;j++) {
      for (int k=0;k<2;k++) {
        //cout << i sp j sp k sp dp[i][j][k] << endl;
      }
    }
  }
  int x = min(dp[1][0][0],dp[1][1][0]);
  cout << (x>=1e9?"impossible":to_string(x)) << endl;
}
    
                  
                             
signed main() { 
  ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
  #ifdef Local
  freopen("in","r",stdin);
  freopen("out","w",stdout); 
  #endif
  int t = 1;
  //cin >> t;
	F(i,t) solve();
}

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 6492 KB Output is correct
2 Correct 2 ms 6492 KB Output is correct
3 Correct 2 ms 6492 KB Output is correct
4 Correct 2 ms 6492 KB Output is correct
5 Correct 2 ms 6492 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 6492 KB Output is correct
2 Correct 2 ms 6492 KB Output is correct
3 Correct 2 ms 6492 KB Output is correct
4 Correct 2 ms 6492 KB Output is correct
5 Correct 2 ms 6492 KB Output is correct
6 Correct 2 ms 6492 KB Output is correct
7 Correct 2 ms 6492 KB Output is correct
8 Correct 2 ms 6732 KB Output is correct
9 Correct 2 ms 6492 KB Output is correct
10 Correct 2 ms 6492 KB Output is correct
11 Correct 2 ms 6492 KB Output is correct
12 Correct 2 ms 6664 KB Output is correct
13 Correct 2 ms 6492 KB Output is correct
14 Correct 2 ms 6492 KB Output is correct
15 Correct 2 ms 6492 KB Output is correct
16 Correct 2 ms 6492 KB Output is correct

Subtask #3
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 51 ms 25180 KB Output is correct
2 Correct 56 ms 25036 KB Output is correct
3 Correct 75 ms 25388 KB Output is correct

Subtask #4
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 53 ms 25200 KB Output is correct
2 Correct 53 ms 25180 KB Output is correct
3 Correct 58 ms 25712 KB Output is correct
4 Correct 44 ms 10288 KB Output is correct
5 Correct 70 ms 10640 KB Output is correct
6 Correct 58 ms 10696 KB Output is correct
7 Correct 3 ms 6904 KB Output is correct
8 Correct 23 ms 7952 KB Output is correct
9 Correct 47 ms 10332 KB Output is correct
10 Correct 51 ms 10548 KB Output is correct
11 Correct 47 ms 11356 KB Output is correct
12 Correct 57 ms 11636 KB Output is correct
13 Correct 53 ms 10584 KB Output is correct
14 Correct 49 ms 11032 KB Output is correct

Subtask #5
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 6492 KB Output is correct
2 Correct 2 ms 6492 KB Output is correct
3 Correct 2 ms 6492 KB Output is correct
4 Correct 2 ms 6492 KB Output is correct
5 Correct 2 ms 6492 KB Output is correct
6 Correct 2 ms 6492 KB Output is correct
7 Correct 2 ms 6492 KB Output is correct
8 Correct 2 ms 6732 KB Output is correct
9 Correct 2 ms 6492 KB Output is correct
10 Correct 2 ms 6492 KB Output is correct
11 Correct 2 ms 6492 KB Output is correct
12 Correct 2 ms 6664 KB Output is correct
13 Correct 2 ms 6492 KB Output is correct
14 Correct 2 ms 6492 KB Output is correct
15 Correct 2 ms 6492 KB Output is correct
16 Correct 2 ms 6492 KB Output is correct
17 Correct 51 ms 25180 KB Output is correct
18 Correct 56 ms 25036 KB Output is correct
19 Correct 75 ms 25388 KB Output is correct
20 Correct 53 ms 25200 KB Output is correct
21 Correct 53 ms 25180 KB Output is correct
22 Correct 58 ms 25712 KB Output is correct
23 Correct 44 ms 10288 KB Output is correct
24 Correct 70 ms 10640 KB Output is correct
25 Correct 58 ms 10696 KB Output is correct
26 Correct 3 ms 6904 KB Output is correct
27 Correct 23 ms 7952 KB Output is correct
28 Correct 47 ms 10332 KB Output is correct
29 Correct 51 ms 10548 KB Output is correct
30 Correct 47 ms 11356 KB Output is correct
31 Correct 57 ms 11636 KB Output is correct
32 Correct 53 ms 10584 KB Output is correct
33 Correct 49 ms 11032 KB Output is correct
34 Correct 2 ms 6492 KB Output is correct
35 Correct 2 ms 6492 KB Output is correct
36 Correct 2 ms 6492 KB Output is correct
37 Correct 2 ms 6492 KB Output is correct
38 Correct 2 ms 6492 KB Output is correct
39 Correct 2 ms 6492 KB Output is correct
40 Correct 2 ms 6488 KB Output is correct
41 Correct 2 ms 6492 KB Output is correct
42 Correct 2 ms 6492 KB Output is correct
43 Correct 2 ms 6492 KB Output is correct
44 Correct 2 ms 6492 KB Output is correct
45 Correct 56 ms 25396 KB Output is correct
46 Correct 59 ms 25136 KB Output is correct
47 Correct 53 ms 25424 KB Output is correct
48 Correct 55 ms 10208 KB Output is correct
49 Correct 52 ms 10640 KB Output is correct
50 Correct 67 ms 10576 KB Output is correct
51 Correct 2 ms 6744 KB Output is correct
52 Correct 17 ms 8028 KB Output is correct
53 Correct 52 ms 10464 KB Output is correct
54 Correct 68 ms 10440 KB Output is correct
55 Correct 68 ms 11344 KB Output is correct
56 Correct 57 ms 11764 KB Output is correct
57 Correct 43 ms 10584 KB Output is correct
58 Correct 47 ms 10836 KB Output is correct
59 Correct 17 ms 7768 KB Output is correct
60 Correct 71 ms 10072 KB Output is correct
61 Correct 49 ms 10320 KB Output is correct
62 Correct 54 ms 10332 KB Output is correct
63 Correct 49 ms 10328 KB Output is correct
64 Correct 49 ms 10228 KB Output is correct
65 Correct 45 ms 10844 KB Output is correct
66 Correct 42 ms 10840 KB Output is correct
67 Correct 41 ms 12352 KB Output is correct
68 Correct 51 ms 12456 KB Output is correct
69 Correct 40 ms 12392 KB Output is correct
70 Correct 44 ms 12412 KB Output is correct