oj.uz

Submission #793130

# Submission time Handle Problem Language Result Execution time Memory
793130 2023-07-25T14:14:42 Z anton Power Plant (JOI20_power) C++17
0 / 100
 2 ms 4948 KB 
#include<bits/stdc++.h>

using namespace std;
#define int long long

const int MAX_N = 2*1e5;
int n, dp[MAX_N][2];
string s;
vector<int> adj[MAX_N];

void dfs(int id, int anc){
    for(int i = 0; i<adj[id].size(); i++){
        if(adj[id][i] == anc){
            adj[id].erase(adj[id].begin() +i);
            break;
        }
    }

    for(auto e: adj[id]){
        dfs(e, id);
    }
}


void find_dp(int id){
    dp[id][0] = dp[id][1] = 0;

    bool gen = s[id] == '1';

    int s1=0;
    int best1= 0;

    int best0= 0;

    for(auto e: adj[id]){
        find_dp(e);
        s1 += dp[e][1];
        best1 = max(best1, dp[e][1]);
        best0 = max(best0, dp[e][0]);
    }
    if(!gen){
        dp[id][0] = max(best0, 0LL);
        dp[id][1] = max(s1, 0LL);
    }
    else{
        dp[id][0] = max(s1-1, max(best1+1, 1LL));
        dp[id][1] = max(s1-1, 1LL);
    }

    //cout<<id<<" "<<dp[id][0]<<" "<<dp[id][1]<<endl;
}


signed main(){
    cin>>n;

    for(int i = 0; i<n-1; i++){
        int a, b;
        cin>>a>>b;
        a--;b--;
        adj[a].push_back(b);
        adj[b].push_back(a);
    }

    dfs(0, -1);

    cin>>s;

    find_dp(0);
    cout<<dp[0][0]<<endl;
}

Compilation message

power.cpp: In function 'void dfs(long long int, long long int)':
power.cpp:12:21: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   12 |     for(int i = 0; i<adj[id].size(); i++){
      |                    ~^~~~~~~~~~~~~~~

Subtask #1
0.0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 4948 KB Output is correct
2 Correct 2 ms 4948 KB Output is correct
3 Incorrect 2 ms 4948 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #2
0.0 / 41.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 4948 KB Output is correct
2 Correct 2 ms 4948 KB Output is correct
3 Incorrect 2 ms 4948 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #3
0.0 / 53.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 4948 KB Output is correct
2 Correct 2 ms 4948 KB Output is correct
3 Incorrect 2 ms 4948 KB Output isn't correct
4 Halted 0 ms 0 KB -