#d1503. 选数2

选数2

Selecting Numbers 2

Problem Description

Given NN numbers, little t wants to select some of them so that the maximum of the selected numbers is less than or equal to kk times their average.

Little t wants to select as many numbers as possible. Find how many numbers can never be selected.

Let MM be the maximum number of numbers that can be selected. A number can never be selected if and only if it does not appear in any scheme that selects MM numbers.

Input Format

The first line contains a positive integer NN, the number of numbers.

The next line contains NN positive integers, the NN numbers, separated by spaces.

The last line contains two positive integers pp and qq, representing kk (k=pqk = \frac{p}{q} and k>1k > 1).

Output Format

The first line outputs MM, the number of numbers that can never be selected.

The next line outputs the MM positive integers, the indices of the unselectable numbers in the original sequence, sorted in ascending order, separated by spaces.

Sample Input 1

4
1 2 3 4
3 2

Sample Output 1

0

Sample Input 2

5
1 15 2 5 1
2 1

Sample Output 2

1
2

Sample Input 3

5
1 2 3 1000 10000
4 3

Sample Output 3

2
4 5

Sample Explanation

In sample 1, we can select at most 3 numbers. And for any number, there is a scheme selecting 3 numbers that includes it, so there is no unselectable number.

Constraints

For all data: 1≤n≤2⋅1051 \le n \le 2 \cdot 10^5, 0≤ai≤1090 \le a_i \le 10^9, 1≤q<p≤10001 \le q < p \le 1000.

Hint

Some approaches look correct but are actually not quite right. You might want to prove it before coding.