제출 #681351

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
681351		YENGOYAN	A Difficult(y) Choice (BOI21_books)	C++17	45 / 100	2 ms	1104 KiB

books

#include <bits/stdc++.h>

#include "books.h"

using namespace std;
using ll = long long;
//
// --- Sample implementation for the task books ---
//
// To compile this program with the sample grader, place:
//     books.h books_sample.cpp sample_grader.cpp
// in a single folder and run:
//     g++ books_sample.cpp sample_grader.cpp
// in this folder.
//

void solve(int n, int k, long long a, int s) {
    // TODO implement this function
    vector<long long> vec(n);
    long long sm = 0;
    for (int i = 0; i < k - 1; ++i) vec[i] = skim(i + 1), sm += vec[i];
    int l = k - 2, r = n - 1;
    while (l + 1 < r) {
        int m = (l + r) / 2;
        long long b = vec[m];
        if (!b) b = skim(m + 1);
        vec[m] = b;
        if (sm + b >= a) r = m;
        else l = m;
    }
    if (sm + vec[r] > 2 * a || sm + vec[r] < a) {
        l = -1, r = n;
        while (l + 1 < r) {
            int m = (l + r) / 2;
            sm = 0;
            if (m + k > n) {
                r = m;
                continue;
            }
            if (!vec[m]) vec[m] = skim(m + 1);
            if (1ll * vec[m] * k > 2ll * a) {
                r = m;
                continue;
            }
            if (!vec[m + k - 1]) vec[m + k - 1] = skim(m + k);
            if (1ll * vec[m + k - 1] * k < a) {
                l = m;
                continue;
            }
            for (int i = m; i < m + k; ++i) {
                if (!vec[i]) vec[i] = skim(i + 1);
                sm += vec[i];
            }
            if (sm >= a)  r = m;
            else l = m;
        }
        sm = 0;
        if (r + k > n) {
            impossible();
            return;
        }
        for (int i = r; i < r + k; ++i) sm += vec[i];
        if (sm < a || sm > 2 * a) impossible();
        else {
            vector<int> ans;
            for (int i = r + 1; i <= r + k; ++i) ans.push_back(i);
            answer(ans);
        }
        return;
    }
    vector<int> ans;
    for (int i = 1; i <= k - 1; ++i) ans.push_back(i);
    ans.push_back(r + 1);
    answer(ans);
}

• Subtask 1: 5 / 5
• Subtask 2: 15 / 15
• Subtask 3: 10 / 10
• Subtask 4: 15 / 15
• Subtask 5: 0 / 15
• Subtask 6: 0 / 20
• Subtask 7: 0 / 20