Submission #530159

#	Time	Username	Problem	Language	Result	Execution time	Memory
530159		benedict0724	A Difficult(y) Choice (BOI21_books)	C++17	100 / 100	1 ms	288 KiB

books

#include <bits/stdc++.h>

#include "books.h"

using namespace std;

void solve(int N, int K, long long A, int S) {
    int l = 1, r = N+1;
    while(l < r)
    {
        int mid = (l + r)/2;
        if(skim(mid) > A) r = mid;
        else l = mid + 1;
    }
    if(l < K)
    {
        impossible();
        return;
    }
    if(l == K)
    {
        long long ans = 0;
        for(int i=1;i<=K;i++) ans += skim(i);
        vector<int> v;
        for(int i=1;i<=K;i++) v.push_back(i);
        if(A <= ans && ans <= 2*A) answer(v);
        else impossible();
        return;
    }

    long long a[11], b[11];
    for(int i=1;i<=K;i++)
    {
        a[i] = skim(i);
        b[i] = skim(l-K+i-1);
    }

    long long ans = 0;
    vector<int> v;
    if(l <= N)
    {
        for(int i=1;i<K;i++) ans += a[i];
        ans += skim(l);
        if(A <= ans && ans <= 2*A)
        {
            for(int i=1;i<K;i++) v.push_back(i);
            v.push_back(l);
            answer(v);
            return;
        }
    }

    ans = 0;
    for(int i=1;i<=K;i++) ans += a[i];
    if(ans > 2*A)
    {
        impossible();
        return;
    }
    for(int i=1;i<=K;i++) v.push_back(i);
    for(int i=K;i>=0;i--)
    {
        if(A <= ans && ans <= 2*A)
        {
            answer(v);
            return;
        }
        if(i == 0) break;
        v[i-1] = l-K+i-1;
        ans += b[i] - a[i];
    }
    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