Submission #1293791

#	Time	Username	Problem	Language	Result	Execution time	Memory
1293791		darkdevilvaqif	Paprike (COI18_paprike)	C++20	100 / 100	38 ms	20748 KiB

paprike

#pragma GCC optimize("O3")
#pragma GCC optimize ("unroll-loops")
// #pragma GCC target("avx2")
#include <bits/stdc++.h>
#define ll long long
#define ull unsigned ll
#define ld long double
#define all(v, l) v.begin() + l, v.end()
#define rall(v, l) v.rbegin(), v.rend() - l
#define pb push_back
#define pf push_front
#define rsz resize
#define fi first
#define se second
#define LMAX LLONG_MAX
#define LMIN LLONG_MIN
#define IMAX INT_MAX
#define IMIN INT_MIN
#define endl "\n"
#define newline cout << endl;
using namespace std;
 
// structs
struct graph
{
    vector <vector <int> > g;
    vector <ll> lvl;
    
    void prep(int n)
    {
        g.rsz(n);
        lvl.rsz(n);
    }
    
    ll limit;
    int cnt;
    void DFS(int v, int par)
    {
        vector <ll> choices;
        for (auto u : g[v])
        {
            if (par == u)
            {
                continue;
            }
            
            DFS(u, v);
            choices.pb(lvl[u]);
        }
        
        sort(all(choices, 0));
        int sz = (int)choices.size();
        for (int i = 0; i < sz; i++)
        {
            if (lvl[v] + choices[i] > limit)
            {
                cnt += sz - i;
                break;
            }
            else
            {
                lvl[v] += choices[i];
            }
        }
    }
    
    void cleanse()
    {
        cnt = 0;
    }
};

// globals

// variables
int n;
ll k;

// iterators
int i;

// notes
/*
 -stuff you should look for-
* int overflow, array bounds
* special cases (n=1?)
* do something instead of nothing and stay organized
* WRITE STUFF DOWN
* DON'T GET STUCK ON ONE APPROACH

continue - skip the rest in the loop
*/

// functions
ll GCD(ll numeroune, ll numerodeux);
ll LCM(ll numeroune, ll numerodeux);
ll power(ll numeroune, ll numerodeux);
 
void solve()
{
    graph G;
    cin >> n >> k;
    G.prep(n + 1);
    for (i = 1; i <= n; i++)
    {
        cin >> G.lvl[i];
    }
    for (i = 1; i < n; i++)
    {
        int u, v;
        cin >> u >> v;
        G.g[u].pb(v);
        G.g[v].pb(u);
    }
    
    G.cleanse();
    G.limit = k;
    G.DFS(1, -1);
    
    cout << G.cnt;
}
 
int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    int t = 1;
    // cin >> t;
    while (t--)
    {
        solve();
        newline
    }
}
 
ll GCD(ll numeroune, ll numerodeux)
{
    if (!numeroune)
    {
        return numerodeux;
    }
    return GCD(numerodeux % numeroune, numeroune);
}

ll LCM(ll numeroune, ll numerodeux)
{
    return numeroune * numerodeux / GCD(numeroune, numerodeux);
}

ll power(ll numeroune, ll numerodeux)
{
    ll res = 1;
    while (numerodeux) 
    {
        if (numerodeux & 1)
        { 
            res *= numeroune;
        }
        numeroune *= numeroune;
        numerodeux >>= 1;    
    }
    return res;
}

/*
$$$$$$$$\ $$$$$$$$\ 
$$  _____|\____$$  |
$$ |          $$  / 
$$$$$\       $$  /  
$$  __|     $$  /   
$$ |       $$  /    
$$$$$$$$\ $$$$$$$$\ 
\________|\________|
*/

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