Problem:
Score : 400 points

Problem Statement

Takahashi is going to buy N items one by one.

The price of the i-th item he buys is A_i yen (the currency of Japan).

He has M discount tickets, and he can use any number of them when buying an item.

If Y tickets are used when buying an item priced X yen, he can get the item for \frac{X}{2^Y} (rounded down to the nearest integer) yen.

What is the minimum amount of money required to buy all the items?

Constraints

All values in input are integers.

1 \leq N, M \leq 10^5

1 \leq A_i \leq 10^9

Input

Input is given from Standard Input in the following format:

N M
A_1 A_2 ... A_N

Output

Print the minimum amount of money required to buy all the items.

Sample Input 1

3 3
2 13 8

Sample Output 1

9

We can buy all the items for 9 yen, as follows:

Buy the 1-st item for 2 yen without tickets.

Buy the 2-nd item for 3 yen with 2 tickets.

Buy the 3-rd item for 4 yen with 1 ticket.

Sample Input 2

4 4
1 9 3 5

Sample Output 2

6

Sample Input 3

1 100000
1000000000

Sample Output 3

0

We can buy the item priced 1000000000 yen for 0 yen with 100000 tickets.

Sample Input 4

10 1
1000000000 1000000000 1000000000 1000000000 1000000000 1000000000 1000000000 1000000000 1000000000 1000000000

Sample Output 4

9500000000

Solution in C# (Mono 4.6.2.0) (judge verdict: Time Limit Exceeded)

using System;
class discount{
  public static void Main(){
    String[] str = Console.ReadLine().Split(' ');
    int n = int.Parse(str[0]); //number of goods
    int m = int.Parse(str[1]); //number of discount ticket
    ulong[] price = new ulong[n];
    str = Console.ReadLine().Split(' ');
    for(int i=0; i<n; i++){
      price[i] = ulong.Parse(str[i]);
    }
    for(int i=0; i<m; i++){
      Array.Sort(price);
      price[n-1] = price[n-1]/2;
    }
    ulong sum=0;
    for(int i=0; i<n; i++){
      sum+=price[i];
    }
    Console.WriteLine(sum);
  }
}