Submission #506376

#	Time	Username	Problem	Language	Result	Execution time	Memory
506376		Elegia	A Difficult(y) Choice (BOI21_books)	C++17	100 / 100	2 ms	304 KiB

books

#include <cmath>
#include <cassert>

#include <algorithm>
#include <bitset>
#include <numeric>
#include <iostream>
#include <vector>
#include <string>
#include <set>
#include <queue>
#include <map>
#include <unordered_map>

#include "books.h"

using namespace std;

long long arr[25];

void solve(int N, int K, long long A, int S) {
	for (int i = 1; i != K; ++i) arr[i] = skim(i);
	long long sum = accumulate(arr + 1, arr + K, 0LL);
	int low = K, high = N + 1;
	while (low < high) {
		int mid = (low + high) / 2;
		if (skim(mid) + sum >= A) high = mid;
		else low = mid + 1;
	}
	if (low <= N && skim(low) + sum <= A * 2) {
		vector<int> ans(K); iota(ans.begin(), ans.end(), 1);
		ans[K - 1] = low;
		return answer(ans);
	}
	if (low == K) return impossible();
	for (int i = 1; i <= K; ++i) {
		sum += skim(low - i) - arr[K + 1 - i];
		if (sum >= A) {
			vector<int> ans(K); iota(ans.begin(), ans.end() - i, 1);
			iota(ans.end() - i, ans.end(), low - i);
			return answer(ans);
		}
	}
	impossible();
}

• Subtask 1: 5 / 5
• Subtask 2: 15 / 15
• Subtask 3: 10 / 10
• Subtask 4: 15 / 15
• Subtask 5: 15 / 15
• Subtask 6: 20 / 20
• Subtask 7: 20 / 20