Submission #619945

#	Time	Username	Problem	Language	Result	Execution time	Memory
619945		nohaxjustsoflo	Power Plant (JOI20_power)	C++17	0 / 100	5 ms	7380 KiB

power

#include <bits/stdc++.h>
#include <iostream>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
typedef tree<ll,null_type,less_equal<ll>,rb_tree_tag,tree_order_statistics_node_update> order_set;
mt19937 mt_rand(chrono::high_resolution_clock::now().time_since_epoch().count());
//uniform_int_distribution<int> gen; ///(min, max)
//int random() {return gen(mt_rand);}
const int mxN=3e5+5;
const int mod=998244353;
const int mxlogN=20;
const int mxK=26;
const int inf=2e9;
const int K=600;
vector<int> adj[mxN];
string s;
int dp[2][mxN];
int solve(int i, bool b, int p)
{
    if(~dp[b][i]) return dp[b][i];
    if(!b)
    {
        int ans=0, ans2=0, ans3=0;
        for(int j:adj[i])
        {
            if(j==p) continue;
            ans=max(ans,solve(j,0,i));
            ans2=max(ans2,solve(j,1,i));
            ans3+=solve(j,1,i);
        }
        ans=max(ans,ans3);
        if(s[i]=='1') ans=max(ans,ans2+1);
        return dp[b][i]=ans;
    }
    int ans=0, ans2=0;
    if(s[i]=='1') ans=1;
    for(int j:adj[i])
    {
        if(j==p) continue;
        ans2+=solve(j,1,i);
    }
    ans=max(ans,ans2-(s[i]=='1'));
    return dp[b][i]=ans;
}
int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);

    int n; cin >> n;
    for(int i=0; i<n; i++) dp[0][i]=dp[1][i]=-1;
    for(int i=1; i<n; i++)
    {
        int u,v; cin >> u >> v; u--, v--;
        adj[u].push_back(v);
        adj[v].push_back(u);
    }
    cin >> s;
    cout << solve(0,0,0) << "\n";
}

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