Submission #413106

#	Time	Username	Problem	Language	Result	Execution time	Memory
413106		atoiz	Packing Biscuits (IOI20_biscuits)	C++14	12 / 100	18 ms	1100 KiB

biscuits

#include "biscuits.h"
#include <numeric>
#include <cstdio>

long long count_tastiness(long long x, std::vector<long long> a) {
	int k = (int) a.size();
	std::vector<long long> dp(k + 1);
	std::vector<int> flag(k + 1, true);
	dp[0] = 1;
	for (int i = 0; i < k; ++i) {
		std::vector<int> digit(i);
		long long cur = 0;
		for (int j = 0; j < i; ++j) {
			cur += a[j];
			digit[j] = (cur & 1);
			cur /= 2;
		}	
		cur += a[i];
		dp[i + 1] = dp[i];
		
		if (cur < x) {
			flag[i] = false;
			continue;
		}

		if (i < k - 1 && cur >= 2 * x) {
			dp[i + 1] *= 2;
			continue;
		}

		// fprintf(stderr, "i = %d, cur = %lld\n", i, cur);
		dp[i + 1] *= (cur / x);
		cur %= x;
		// fprintf(stderr, "i = %d, cur = %lld, dp[i + 1] = %lld\n", i, cur, dp[i + 1]);
		
		bool tmp = true;
		for (int j = i - 1; j >= 0; --j) {
			cur = cur * 2 + digit[j];
			if (cur >= x) {
				dp[i + 1] += dp[j];
				if (!flag[j]) {
					tmp = false;
					break;
				}
				cur -= x;
			}
		}
		dp[i + 1] += tmp;
	}

	// for (int i = 0; i <= k; ++i) {
		// fprintf(stderr, "dp[1 << %d == %lld] = %lld\n", i, 1ll << i, dp[i]);
	// }

	return dp[k];
}

• Subtask 1: 0 / 9
• Subtask 2: 12 / 12
• Subtask 3: 0 / 21
• Subtask 4: 0 / 35
• Subtask 5: 0 / 23