Submission #233094

#	Time	Username	Problem	Language	Result	Execution time	Memory
233094		PeppaPig	Paprike (COI18_paprike)	C++14	100 / 100	96 ms	17656 KiB

paprike

#include <bits/stdc++.h>

using namespace std;

const int N = 1e5+5;

int n, k, ans, A[N];
vector<int> g[N];

int dfs(int u, int p) {
    int sum = A[u];
    vector<int> vec;
    for(int v : g[u]) if(v != p)
        vec.emplace_back(dfs(v, u));
    sort(vec.begin(), vec.end());
    for(int i = 0; i < vec.size(); i++) {
        if(sum + vec[i] > k) ++ans;
        else sum += vec[i];
    }
    return sum;
}

int main() {
    scanf("%d %d", &n, &k);
    for(int i = 1; i <= n; i++) scanf("%d", A + i);
    for(int i = 1, a, b; i < n; i++) {
        scanf("%d %d", &a, &b);
        g[a].emplace_back(b);
        g[b].emplace_back(a);
    }
    dfs(1, 0);
    printf("%d\n", ans);

    return 0;
}

Compilation message (stderr)

paprike.cpp: In function 'int dfs(int, int)':
paprike.cpp:16:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i = 0; i < vec.size(); i++) {
                    ~~^~~~~~~~~~~~
paprike.cpp: In function 'int main()':
paprike.cpp:24:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %d", &n, &k);
     ~~~~~^~~~~~~~~~~~~~~~~
paprike.cpp:25:38: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     for(int i = 1; i <= n; i++) scanf("%d", A + i);
                                 ~~~~~^~~~~~~~~~~~~
paprike.cpp:27:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d %d", &a, &b);
         ~~~~~^~~~~~~~~~~~~~~~~

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