Submission #818648

#	Time	Username	Problem	Language	Result	Execution time	Memory
818648		kevinsogo	Packing Biscuits (IOI20_biscuits)	C++17	100 / 100	40 ms	51708 KiB

biscuits

#include <bits/stdc++.h>
using namespace std;
#include "biscuits.h"
using ll = long long;
using lll = __int128;

struct node {
    lll mn, mx, ad, sz;
    node *l, *r;
};
using seq = node*;
seq con(lll n, lll v) {
    return n == 0 ? nullptr : new node{v, v, 0, n, nullptr, nullptr};
}
seq inc(seq s, lll a) {
    return a == 0 ? s : new node{s->mn, s->mx, s->ad + a, s->sz, s->l, s->r};
}
seq conc(seq l, seq r, lll ad = 0) {
    if (l == nullptr) return inc(r, ad);
    if (r == nullptr) return inc(l, ad);
    assert(l->mx + l->ad <= r->mn + r->ad);
    return new node{l->mn + l->ad, r->mx + r->ad, ad, l->sz + r->sz, l, r};
}
seq drop(seq s, lll u = 0) {
    u -= s->ad;
    return s->mx < u ? nullptr : u <= s->mn ? s : conc(drop(s->l, u), drop(s->r, u), s->ad);
}
lll size(seq s) {
    return s->sz;
}

ll count_tastiness(ll x, vector<ll> a) {
    a.resize(62);
    auto s = con(1, 0);
    for (int i = 0; i < a.size(); i++) s = drop(conc(inc(s, lll(-x) << i), s, lll(a[i]) << i));
    return size(s);
}

Compilation message (stderr)

biscuits.cpp: In function 'll count_tastiness(ll, std::vector<long long int>)':
biscuits.cpp:35:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   35 |     for (int i = 0; i < a.size(); i++) s = drop(conc(inc(s, lll(-x) << i), s, lll(a[i]) << i));
      |                     ~~^~~~~~~~~~

• Subtask 1: 9 / 9
• Subtask 2: 12 / 12
• Subtask 3: 21 / 21
• Subtask 4: 35 / 35
• Subtask 5: 23 / 23