Magician and Chocolates

Given N bags, each bag contains B_i chocolates. There is a kid and a magician. In one unit of time, kid chooses a random bag i, eats B_i chocolates, then the magician fills the ith bag with floor(B_i/2) chocolates.

Find the maximum number of chocolates that kid can eat in A units of time.

NOTE:

1. floor() function returns the largest integer less than or equal to a given number.
2. Return your answer modulo 10⁹+7

First argument is an integer A.
Second argument is an integer array B of size N.

Return an integer denoting the maximum number of chocolates that kid can eat in A units of time.

Input 1:

 A = 3
 B = [6, 5]

Input 2:

 A = 5
 b = [2, 4, 6, 8, 10]

Output 1:

 14

Output 2:

 33

Explanation 1:

 At t = 1 kid eats 6 chocolates from bag 0, and the bag gets filled by 3 chocolates. 
 At t = 2 kid eats 5 chocolates from bag 1, and the bag gets filled by 2 chocolates. 
 At t = 3 kid eats 3 chocolates from bag 0, and the bag gets filled by 1 chocolate. 
 so, total number of chocolates eaten are 6 + 5 + 3 = 14