Submission #312694

#	Time	Username	Problem	Language	Result	Execution time	Memory
312694		Jarif_Rahman	Power Plant (JOI20_power)	C++17	0 / 100	0 ms	384 KiB

power

#include <bits/stdc++.h>
#define pb push_back
#define f first
#define sc second
using namespace std;
typedef long long int ll;
typedef string str;
int n;
str s;
vector <vector<int>> v;
vector <ll> sth, root;
ll ans =  0;
ll dfs1(int nd, int ss){
    ll r = '0'-s[nd];
    if(v[nd].size() == 1 && s[nd] == '1') r = 1;
    for(int x: v[nd]) if(x != ss) r+=dfs1(x, nd);
    sth[nd] = max(r, (ll)s[nd] - '0');
    return sth[nd];
}
void dfs2(int nd, int ss){
    ll sss = sth[nd];
    if(ss != -1){
        root[ss]+=sth[nd];
        sss+=max(sth[ss] - sth[nd], (ll)s[ss] - '0');
    }
    sth[nd] = sss;
    for(int x: v[nd]) if(ss != x){
        sss-=sth[x];
        root[x]+=max(sss, (ll)s[nd] - '0');
        sss+=sth[x];
    }
    for(int x: v[nd]) if(x != ss) dfs2(x, nd);
}
int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cin >> n;
    v = vector<vector<int>> (n+1);
    sth = vector <ll> (n+1, -1);
    root = vector<ll> (n+1, 0);
    for(int i = 1; i < n; i++){
        int a, b; cin >> a >> b;
        v[a].pb(b);
        v[b].pb(a);
    }
    cin >> s;
    s = "x"+s;
    dfs1(1, -1);
    dfs2(1, -1);
    for(int i = 1; i <+ n; i++){
        if(v[i].size() == 1){
            root[i] = max(root[i]+s[i]-'0', (ll)s[i] - '0');
        }
        else root[i] = max(root[i]+'0'-s[i], (ll)s[i] - '0');

    }
 	for(int i = 1; i <= n; i++) ans = max(ans, root[i]);
    cout << ans << "\n";
}

• Subtask 1: 0 / 6
• Subtask 2: 0 / 41
• Subtask 3: 0 / 53