Submission #240804

#	Time	Username	Problem	Language	Result	Execution time	Memory
240804		ne4eHbKa	Paprike (COI18_paprike)	C++17	100 / 100	81 ms	23928 KiB

paprike

//{ <defines>
#include <bits/stdc++.h>
using namespace std;

//#pragma comment(linker, "/stack:200000000")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
//#pragma GCC optimize("Ofast,no-stack-protector,unroll-loops,fast-math,-O3")

#define fr(i, n) for(int i = 0; i < n; ++i)
#define fo(n) fr(i, n)

#define re return
#define ef else if
#define ifn(x) if(!(x))
#define _  << ' ' <<

#define ft first
#define sd second
#define ve vector
#define pb push_back
#define eb emplace_back

#define sz(x) int((x).size())
#define bnd(x) x.begin(), x.end()
#define clr(x, y) memset((x), (y), sizeof (x))

typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef ve<int> vi;

inline ll time() {re chrono :: system_clock().now().time_since_epoch().count();}
mt19937 rnd(time());
mt19937_64 RND(time());

template<typename t> inline void umin(t &a, t b) {a = min(a, b);}
template<typename t> inline void umax(t &a, t b) {a = max(a, b);}

int md = 998244353;

inline int m_add(int&a, int b) {a += b; if(a < 0) a += md; if(a >= md) a -= md; re a;}
inline int m_sum(int a, int b) {a += b; if(a < 0) a += md; if(a >= md) a -= md; re a;}
inline int m_mul(int&a, int b) {re a = 1ll * a * b % md;}
inline int m_prod(int a, int b) {re 1ll * a * b % md;}

int m_bpow(ll A, ll b) {
    int a = A % md;
    ll ans = 1;
    for(ll p = 1ll << 63 - __builtin_clzll(b); p; p >>= 1) {
        (ans *= ans) %= md;
        if(p & b)
            (ans *= a) %= md;
    }
    re ans;
}

const ld pi = arg(complex<ld>(-1, 0));
const ld pi2 = pi + pi;
const int oo = 2e9;
const ll OO = 4e18;
//} </defines>
const int N = 1e5 + 5;

int n, h[N], k;
vi g[N];

pii rec(int v = 0, int pr = -1) {
    int f = 0;
    ll s = 0;
    vector<int> t;
    t.reserve(sz(g[v]) + 1);
    for(int u : g[v]) {
        if(u == pr) continue;
        pii e = rec(u, v);
        f += e.ft;
        t.pb(e.sd);
    }
    sort(t.rbegin(), t.rend());
    t.pb(h[v]);
    for(int i : t) s += i;
    for(int i = 0; s > k; ++i) s -= t[i], ++f;
    return {f, s};
}

void solve() {
    cin >> n >> k;
    for(int i = 0; i < n; ++i) cin >> h[i], g[i].clear();
    for(int i = 1; i < n; ++i) {
        int x, y;
        cin >> x >> y;
        --x, --y;
        g[x].pb(y);
        g[y].pb(x);
    }
    cout << rec().ft << endl;
}

int main() {
    cout.precision(10); cout << fixed;
    cerr.precision(6); cerr << fixed;
#ifdef _LOCAL
    freopen("in.txt", "r", stdin);
    int tests; cin >> tests;
    for(int test = 1; test <= tests; ++test) {
		cerr << "case #" << test << endl;
        solve();
        cerr << endl;
    }
#else
//    freopen("input.txt", "r", stdin); freopen("output.txt", "w", stdout);
    ios_base :: sync_with_stdio(0); cin.tie(0); cout.tie(0);
    solve();
#endif
    return 0;
}

Compilation message (stderr)

paprike.cpp: In function 'int m_bpow(ll, ll)':
paprike.cpp:50:26: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
     for(ll p = 1ll << 63 - __builtin_clzll(b); p; p >>= 1) {
                       ~~~^~~~~~~~~~~~~~~~~~~~

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