Submission #1307058

#	Time	Username	Problem	Language	Result	Execution time	Memory
1307058		chithanhnguyen	Power Plant (JOI20_power)	C++20	100 / 100	82 ms	26892 KiB

power

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

#define int long long
#define ull unsigned long long
#define ld long double
#define pii pair<int, int>
#define fi first
#define se second
#define __builtin_popcount __builtin_popcountll
#define all(x) (x).begin(), (x).end()
#define BIT(x, i) (((x) >> (i)) & 1)
#define MASK(x) ((1ll << (x)))

#define debug(a, l, r) for (int _i = (l); _i <= (r); ++_i) cout << (a)[_i] << ' '; cout << '\n';

const int MAXN = 2e5 + 5;
int n, dp[MAXN], res = 0;
string s;
vector<int> adj[MAXN];

void dfs(int u, int par = -1) {
    int cand = - (s[u] == '1');

    for (int v : adj[u]) {
        if (v == par) continue;
        dfs(v, u);
        res = max(res, (s[u] == '1') + dp[v]);
        cand += dp[v];
    }

    dp[u] = max((int)(s[u] == '1'), cand);
}

signed main() {
    #ifdef NCTHANH
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
    #endif
    ios_base::sync_with_stdio(0);
    cin.tie(nullptr); cout.tie(nullptr);

    cin >> n;
    for (int i = 1; i < n; ++i) {
        int u, v; cin >> u >> v;
        adj[u].push_back(v);
        adj[v].push_back(u);
    }
    cin >> s; s = ' ' + s;

    dfs(1);
    cout << max(res, *max_element(dp + 1, dp + n + 1));

    return 0;
}

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