Submission #939533

#	Time	Username	Problem	Language	Result	Execution time	Memory
939533		LucaIlie	A Difficult(y) Choice (BOI21_books)	C++17	60 / 100	1 ms	848 KiB

books

#include <bits/stdc++.h>

#include "books.h"

using namespace std;

const int MAX_N = 1e5;
long long d[MAX_N + 1];

long long dif( int i ) {
    if ( d[i] == 0 )
        d[i] = skim( i );
    return d[i];
}

void solve( int n, int k, long long a, int q ) {
    int l, r;

    l = 0, r = n + 1;
    while ( r - l > 1 ) {
        int mid = (l + r) / 2;

        if ( dif( mid ) >= a )
            r = mid;
        else
            l = mid;
    }

    int m = l;

    if ( m != n ) {
        long long s = dif( m + 1 );
        vector<int> ans;
        ans.push_back( m + 1 );
        for ( int i = 1; i < k; i++ ) {
            s += dif( i );
            ans.push_back( i );
        }
        if ( s <= 2 * a ) {
            answer( ans );
            return;
        }
    }

    if ( m == 0 ) {
        impossible();
        return;
    }

    l = 0, r = m - k + 2;
    while ( r - l > 1 ) {
        int mid = (l + r) / 2;

        long long s = 0;
        vector<int> ans;
        for ( int i = mid; i < mid + k; i++ ) {
            s += dif( i );
            ans.push_back( i );
        }

        if ( s > 2 * a )
            r = mid;
        else
            l = mid;
    }

    if ( l == 0 ) {
        impossible();
        return;
    }

    long long s = 0;
    vector<int> ans;
    for ( int i = l; i < l + k; i++ ) {
        s += dif( i );
        ans.push_back( i );
    }

    int i = l + k - 1;
    while ( i + 1 <= m && s < a ) {
        i++;
        s += dif( i ) - dif( i - k );
        ans[0] = i;
    }

    if ( s >= a )
        answer( ans );
    else
        impossible();
}

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