Submission #1084792

#	Time	Username	Problem	Language	Result	Execution time	Memory
1084792		anhthi	Power Plant (JOI20_power)	C++14	0 / 100	2 ms	4952 KiB

power

#include <bits/stdc++.h>

using namespace std;

#define fi first
#define se second
#define ll long long
#define mp(x, y) make_pair(x, y)
#define sz(v) ((int) (v).size())
#define all(v) (v).begin(), (v).end()
#define MASK(i) (1LL << (i))
#define BIT(x, y) (((x) >> (y)) & 1)
#define pb push_back
#define max_rng *max_element
#define min_rng *min_element
#define rep(i, n) for(int i = 1, _n = (n); i <= _n; ++i)
#define forn(i, a, b) for(int i = (a), _b = (b); i <= _b; ++i)
#define ford(i, a, b) for(int i = (a), _b = (b); i >= _b; --i)

template <class X, class Y>
    inline bool maximize(X &x, Y y) {
        return (x < y ? x = y, true : false);
    }

template <class X, class Y>
    inline bool minimize(X &x, Y y) {
        return (x > y ? x = y, true : false);
    }

template <class X>
    inline void compress(vector<X> &a) {
        sort(all(a));
        a.resize(unique(all(a)) - a.begin());
    }

int ctz(ll x) { return __builtin_ctzll(x); }
int lg(ll x) { return 63 - __builtin_clzll(x); }
int popcount(ll x) { return __builtin_popcount(x); }

#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;

mt19937_64 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
ll rand(ll l, ll r) {
    return l + abs((ll) rng()) % (r - l + 1);
}

const ll oo = (ll) 1e17;
const int inf = (ll) 2e9 + 7, mod = (ll) 1e9 + 7;

const int mxn = 2e5, mxm = 3e6;
const int LG = 18, BASE = 311;

int n;
char s[mxn + 5];
vector<int> g[mxn + 5];

int ans = 0;
int f[mxn + 5];

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

int main(void) {

    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);

    cin >> n;
    rep(i, n-1) {
        int u, v;
        cin >> u >> v;
        g[u].pb(v);
        g[v].pb(u);
    }
    rep(i, n) cin >> s[i];

    dfs();
    cout << ans;

    return 0;
}

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