Submission #850736

#	Time	Username	Problem	Language	Result	Execution time	Memory
850736		esomer	A Difficult(y) Choice (BOI21_books)	C++17	100 / 100	1 ms	1364 KiB

books

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

using namespace std;

// typedef long long l;

vector<int> get_ans(vector<bool>& in){
    vector<int> ans;
    for(int i = 0; i < (int)in.size(); i++){
        if(in[i]) ans.push_back(i+1);
    }
    return ans;
}

void solve(int N, int K, long long A, int S) {
    vector<long long> v(N, -1);
    vector<bool> in(N, 0);
    long long sum = 0;
    for(int i = 0; i < K; i++){
        v[i] = skim(i+1);
        in[i] = 1;
        sum += v[i];
    }
    if(sum > 2 * A) {impossible(); return;}
    if(sum >= A){
        answer(get_ans(in));
        return;
    }
    if(K == N) {impossible(); return;}
    int low = 0;
    int high = N - 1;
    int bst = N;
    while(low <= high){
        int mid = (low + high) / 2;
        if(v[mid] == -1) v[mid] = skim(mid + 1);
        if(v[mid] >= A){
            bst = mid;
            high = mid - 1;
        }else low = mid + 1;
    }
    if(bst != N && bst >= K){
        if(sum - v[K - 1] + v[bst] <= 2 * A){
            in[K-1] = 0;
            in[bst] = 1;
            answer(get_ans(in));
            return;
        }
    }
    N = bst;
    int ind = N - 1;
    for(int i = K - 1; i >= 0; i--){
        if(v[ind] == -1) v[ind] = skim(ind + 1);
        sum -= v[i];
        sum += v[ind];
        in[i] = 0;
        in[ind] = 1;
        if(sum >= A){
            answer(get_ans(in));
            return;
        }
        ind--;
    }
    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