/ SeriousOJ /

Record Detail

Wrong Answer


  
# Status Time Cost Memory Cost
#1 Accepted 2ms 328.0 KiB
#2 Accepted 2ms 540.0 KiB
#3 Wrong Answer 2ms 344.0 KiB
#4 Wrong Answer 5ms 588.0 KiB

Code

#include<bits/stdc++.h>
#define endl        '\n'
#define F           first
#define S           second
#define pb          push_back
#define yes         cout<<"YES\n"
#define no          cout<<"NO\n"
#define all(x)      x.begin(),x.end()
#define allr(x)     x.rbegin(),x.rend()
#define error1(x)   cerr<<#x<<" = "<<(x)<<endl
#define error2(a,b) cerr<<"("<<#a<<", "<<#b<<") = ("<<(a)<<", "<<(b)<<")\n";
#define coutall(v)  for(auto &it: v) cout << it << " "; cout << endl;
using namespace std;
using ll = long long;
using ld = long double;

void solve() {
    ll n, cnt = 0;
    cin >> n;
    vector<ll> val(n + 1);
    for (int i = 1; i <= n; i++) {
        ll x; cin >> x;
        val[i] = x;
        if(x) ++cnt;
    }
    vector<set<ll>> g(n + 1);
    for(int i = 0; i + 1 < n; i++) {
        ll u, v; cin >> u >> v;
        g[u].insert(v);
        g[v].insert(u);
    }

    priority_queue<ll> pq;
    for(int i = 1; i <= n; i++) {
        if(g[i].size() == 1 && val[i] == 0) pq.push(i);
    }
    while(pq.size()) {
        ll u = pq.top();
        ll v = *g[u].begin();
        g[u].clear();
        g[v].erase(u);
        // cout << u << " ";
        pq.pop();
        if(g[v].size() <= 1 && val[v] == 0) {
            pq.push(v);
        }
    }

    ll ans = 0;
    auto dfs = [&](int u, int par, auto&& self) -> void {
        if(val[u] > 0) --cnt; 
        for(auto &v: g[u]) {
            if(v == par) continue;
            // cout << u << " " << v << endl;
            if(cnt > 0) ++ans;
            self(v, u, self);
            if(cnt > 0) ++ans;
        }
        // cout << u << " => " << c << endl;
    };
    for(int i = 1; i <= n; i++) {
        if(g[i].size() == 1) {
            ans = 0;
            dfs(i, -1, dfs);
            break;
        }
        // cout << i << " = ";
        // coutall(g[i]);
    }
    cout << ans << endl;
    return;
}

signed main() {
    ios::sync_with_stdio(false); cin.tie(0);
    int tc = 1;
    cin >> tc;
    for (int t = 1; t <= tc; t++) {
        // cout << "Case " << t << ": ";
        solve();
    }
    return 0;
}

Information

Submit By
Type
Submission
Problem
P1078 Apple on Tree
Contest
Bangladesh 2.0
Language
C++20 (G++ 13.2.0)
Submit At
2024-08-16 16:55:35
Judged At
2024-11-11 03:13:24
Judged By
Score
4
Total Time
5ms
Peak Memory
588.0 KiB