Submission #1083098

#	Time	Username	Problem	Language	Result	Execution time	Memory
1083098		Tymond	Power Plant (JOI20_power)	C++17	100 / 100	71 ms	31636 KiB

power

#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
#define fi first
#define se second
#define vi vector<int>
#define vll vector<long long>
#define pii pair<int, int>
#define pll pair<long long, long long>
#define pb push_back
#define mp make_pair
#define eb emplace_back
#define all(x) (x).begin(), (x).end()
#define sz(x) (int)(x).size()
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
mt19937_64 rng64(chrono::steady_clock::now().time_since_epoch().count());
inline int rand(int l,int r){return uniform_int_distribution<int>(l, r)(rng);}
inline ll rand(ll l,ll r){return uniform_int_distribution<ll>(l, r)(rng64);}
#ifdef DEBUG
auto&operator<<(auto&o,pair<auto,auto>p){return o<<"("<<p.first<<", "<<p.second<<")";}
auto operator<<(auto&o,auto x)->decltype(x.end(),o){o<<"{";int i=0;for(auto e:x)o<<","+!i++<<e;return o<<"}";}
#define debug(X...)cerr<<"["#X"]: ",[](auto...$){((cerr<<$<<"; "),...)<<endl;}(X)
#else
#define debug(...){}
#endif

struct custom_hash {
    static uint64_t splitmix64(uint64_t x) {
        x += 0x9e3779b97f4a7c15;
        x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9;
        x = (x ^ (x >> 27)) * 0x94d049bb133111eb;
        return x ^ (x >> 31);
    }

    size_t operator()(uint64_t x) const {
        static const uint64_t FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count();
        return splitmix64(x + FIXED_RANDOM);
    }
};

const int MAXN = 2e5 + 7;
vi g[MAXN];
int dp[MAXN];
string s;
int n;
int ans = 1;

void dfs(int v, int p){
    dp[v] = (s[v - 1] - '0');
    ans = max(ans, dp[v]);
    int sum = 0;
    int mx = 0;
    for(auto u : g[v]){
        if(u != p){
            dfs(u, v);
            mx = max(mx, dp[u]);
            if(s[v - 1] == '0'){
                dp[v] += dp[u];
            }else{
                sum += dp[u];
            }
        }
    }

    if(s[v - 1] == '1'){
        dp[v] = max(1, sum - 1);
        ans = max(ans, mx + 1);
    }
    //cout << v << ' ' << dp[v] << '\n';
    ans = max(ans, dp[v]);
}

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    
    cin >> n;
    for(int i = 1; i < n; i++){
        int u, v;
        cin >> u >> v;
        g[u].pb(v);
        g[v].pb(u);
    }
    cin >> s;
    ans = 1;
    dfs(1, 1);
    cout << ans << '\n';

    return 0;
}

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