Submission #675170

#	Time	Username	Problem	Language	Result	Execution time	Memory
675170		Cookie	Paprike (COI18_paprike)	C++14	100 / 100	57 ms	21084 KiB

paprike

#include<bits/stdc++.h>

using namespace std;
#include<fstream>

#define ll long long
#define vt vector
#define pb push_back
#define fi first
#define se second
#define forr(i, a, b) for(int i = a; i < b; i++)
#define dorr(i, a, b) for(int i = a; i >= b; i--)
typedef unsigned long long ull;
#define pii pair<int, int>
#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
const ll mod=  1e9 + 7;
const int mxk = 1e3, sq = 750, mxn = 1e5;
const ll inf = -1e18;
ll n, k;
ll d[mxn + 1], w[mxn + 1], a[mxn + 1];
vt<int>adj[mxn + 1];
void dfs(int s, int pre){
    vt<ll>v;
    d[s] = 0;
    for(auto i: adj[s]){
        if(i != pre){
            dfs(i, s); d[s] += d[i];
            v.pb(w[i]);
        }
    }
    sort(v.begin(), v.end());
    w[s] = a[s]; int last = v.size();
    for(int i = 0; i < v.size(); i++){
        if(w[s] + v[i] <= k){
            w[s] += v[i];
        }else{
            last = i; break;
        }
    }
    d[s] += v.size() - last;
}
signed main(){
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    cin >> n >> k;
    for(int i = 1; i <= n; i++)cin >> a[i];
    forr(i, 1, n){
        int u, v; cin >> u >> v;
        adj[u].pb(v); adj[v].pb(u);
    }
    dfs(1, -1);
    cout << d[1];
    return(0);
}

Compilation message (stderr)

paprike.cpp: In function 'void dfs(int, int)':
paprike.cpp:34:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   34 |     for(int i = 0; i < v.size(); i++){
      |                    ~~^~~~~~~~~~

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