Submission #767155

#	Time	Username	Problem	Language	Result	Execution time	Memory
767155		bachhoangxuan	Power Plant (JOI20_power)	C++17	100 / 100	139 ms	40780 KiB

power

// Judges with GCC >= 12 only needs Ofast
// #pragma GCC optimize("O3,no-stack-protector,fast-math,unroll-loops,tree-vectorize")
// MLE optimization
// #pragma GCC optimize("conserve-stack")
// Old judges
// #pragma GCC target("sse4.2,popcnt,lzcnt,abm,mmx,fma,bmi,bmi2")
// New judges. Test with assert(__builtin_cpu_supports("avx2"));
// #pragma GCC target("avx2,popcnt,lzcnt,abm,bmi,bmi2,fma,tune=native")
// Atcoder
// #pragma GCC target("avx2,popcnt,lzcnt,abm,bmi,bmi2,fma")
/*
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
typedef tree<int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update> ordered_set;
- insert(x),erase(x)
- find_by_order(k): return iterator to the k-th smallest element
- order_of_key(x): the number of elements that are strictly smaller
*/
#include<bits/stdc++.h>
using namespace std;
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
uniform_real_distribution<> pp(0.0,1.0);
#define int long long
#define ld long double
#define pii pair<int,int>
#define piii pair<pii,int>
#define mpp make_pair
#define fi first
#define se second
const int inf=1e18;
const int mod=1e9+7;
const int maxn=200005;
const int bl=650;
const int maxs=655;
const int maxm=200005;
const int maxq=500005;
const int maxl=20;
const int maxa=250000;
const int root=3;
int power(int a,int n){
    int res=1;
    while(n){
        if(n&1) res=res*a%mod;
        a=a*a%mod;n>>=1;
    }
    return res;
}
const int iroot=power(3,mod-2);
const int base=101;

void solve(){
    int n;cin >> n;
    vector<vector<int>> edge(n+1);
    vector<int> c(n+1,0),dp(n+1,-inf),dep(n+1,0);
    for(int i=1;i<n;i++){
        int u,v;cin >> u >> v;
        edge[u].push_back(v);
        edge[v].push_back(u);
    }
    for(int i=1;i<=n;i++){char ch;cin >> ch;c[i]=ch-'0';}
    int ans=0;
    function<void(int,int)> dfs = [&](int u,int p){
        dep[u]=dep[p]+c[u];
        int sum=-c[u];
        for(int v:edge[u]){
            if(v==p) continue;
            dfs(v,u);dp[u]=max(dp[u],dp[v]);
            sum+=max(0LL,dp[v]+dep[u]);
        }
        sum=max(sum,c[u]);ans=max(ans,sum);
        ans=max(ans,dp[u]+dep[u]+c[u]);
        dp[u]=max(dp[u],sum-dep[p]);
    };
    dfs(1,0);
    cout << ans << '\n';
}
signed main(){
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);cout.tie(NULL);
    int test=1;//cin >> test;
    while(test--) solve();
}

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