Submission #535821

#	Time	Username	Problem	Language	Result	Execution time	Memory
535821		KoD	Packing Biscuits (IOI20_biscuits)	C++17	100 / 100	214 ms	1356 KiB

biscuits

#include <bits/stdc++.h>
#include "biscuits.h"

using ll = long long;

using std::vector;
using std::array;
using std::pair;

ll count_tastiness(ll x, vector<ll> a) {
	a.resize(60);
	array<ll, 60> max;
	ll sum = 0;
	for (int i = 0; i < 60; ++i) {
		sum += a[i] << i;
		max[i] = sum / x;
	}
	std::map<pair<int, ll>, ll> memo;
	auto dfs = [&](auto&& self, int d, ll y) -> ll {
		y = std::min(y, (1ll << (d + 1)) - 1);
		if (d == -1) {
			return 0;
		}
		if (const auto itr = memo.find(pair(d, y)); itr != memo.end()) {
			return itr->second;
		}
		const ll ub = std::min(max[d], y) - (1ll << d);
		if (ub >= 0) {
			ll ret = 1;
			for (int k = 0; k < d; ++k) {
				ret += self(self, k, ub);
			}
			return memo[{d, y}] = ret;
		} else {
			return memo[{d, y}] = 0;
		}
	};
	ll ret = 1;
	for (int k = 0; k < 60; ++k) {
		ret += dfs(dfs, k, 1ll << 60);
	}
	return ret;
}

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