Submission #105574

#	Time	Username	Problem	Language	Result	Execution time	Memory
105574		keko37	Paprike (COI18_paprike)	C++14	100 / 100	129 ms	21980 KiB

paprike

#include<bits/stdc++.h>

using namespace std;

typedef long long llint;

const int MAXN = 100005;

llint n, k;
llint val[MAXN], dp[MAXN];
vector <int> v[MAXN];

llint dfs (int x, int rod) {
    llint res = val[x];
    vector <llint> r;
    for (int i=0; i<v[x].size(); i++) {
        int sus = v[x][i];
        if (sus == rod) continue;
        r.push_back(dfs(sus, x));
        res += r.back();
        dp[x] += dp[sus];
    }
    sort(r.begin(), r.end());
    while (res > k) {
        res -= r.back();
        dp[x]++;
        r.pop_back();
    }
    return res;
}

int main () {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cin >> n >> k;
    for (int i=1; i<=n; i++) {
        cin >> val[i];
    }
    for (int i=0; i<n-1; i++) {
        int a, b;
        cin >> a >> b;
        v[a].push_back(b);
        v[b].push_back(a);
    }
    dfs(1, 0);
    cout << dp[1];
    return 0;
}

Compilation message (stderr)

paprike.cpp: In function 'llint dfs(int, int)':
paprike.cpp:16:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (int i=0; i<v[x].size(); i++) {
                   ~^~~~~~~~~~~~

• Subtask 1: 11 / 11
• Subtask 2: 13 / 13
• Subtask 3: 27 / 27
• Subtask 4: 49 / 49