Submission #885796

#	Time	Username	Problem	Language	Result	Execution time	Memory
885796		wksp	Power Plant (JOI20_power)	C++14	100 / 100	120 ms	28724 KiB

power

#include<bits/stdc++.h>
using namespace std;

const int n_max = 2 * 1e5 + 7; 
vector<int> graph[n_max];
int power_generator[n_max];
int ans;

int DFS(int v, int p){
    int sum = 0;
    int max_vallue = 0;
    for(auto u: graph[v]){
        if(u != p){
            int vallue = DFS(u ,v);
            sum += vallue;
            max_vallue = max(max_vallue, vallue);
        }
    }
    int ans_tym = 0;
    if(power_generator[v] == 1){
        ans_tym = max(sum - 1, 1);
        if(sum == max_vallue){
            ans = max(ans, sum + 1);
        }
        if(sum == max_vallue + 1){
            ans = max(ans, sum);
        }
    }else{
        ans_tym = sum;
    }
    ans = max(ans, ans_tym);
    return ans_tym;
}


int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    ans = 0;
    int n;
    cin >> n;
    for(int i = 0; i < n - 1; i++){
        int a, b;
        cin >> a >> b;
        graph[a].push_back(b);
        graph[b].push_back(a);
    }
    string s;
    cin >> s;
    for(int i = 0; i < n; i++){
        if(s[i] == '1'){
            power_generator[i+1] = 1;
        }
    }
    ans = 0;
    DFS(1, 0);
    cout << ans << '\n';

    return 0;
}

• Subtask 1: 6 / 6
• Subtask 2: 41 / 41
• Subtask 3: 53 / 53