### BUGGY CODE ###

#141d
from collections import deque
import bisect
import math

N,M = map(int, input().split()) #1≤N,M≤10^5
A_list = list(map(int, input().split()))

#→高額なものに割引券を使った方が良い
if len(A_list) > 1:
    A_list.sort(reverse=False)
    highest = A_list.pop()
    next_highest = A_list[-1]

    discounted_deque = deque()

    while 1:
        #print(A_list,highest)
        
        #highest/(pow(2,X)) <= next_highest に持っていきたい
        #highest <= next_highest * pow(2,X)
        #highest/next_highest <= 2**X
        #log2(highest/next_highest) <= X
        
        use_tickets = math.ceil(math.log(highest/next_highest)/math.log(2))
        if use_tickets == 0:
            use_tickets = 1
        if use_tickets > M:
            use_tickets = M
            
        highest /= pow(2,use_tickets)
        M -= use_tickets
        
        #print(A_list,highest)
        
        if M!= 0:
            discounted_deque.appendleft(highest)
            
            if len(A_list) > 0:
                if A_list[-1] > discounted_deque[-1]:
                    highest = A_list.pop()
                else:
                    highest = discounted_deque.pop()
                
            if len(A_list) > 0 and len(discounted_deque) > 0:
                if A_list[-1] > discounted_deque[-1]:
                    next_highest = A_list[-1]
                else:
                    next_highest = discounted_deque[-1]
            elif len(A_list) == 0 and len(discounted_deque) > 0:
                next_highest = discounted_deque[-1]
            elif len(A_list) > 0 and len(discounted_deque) == 0:
                next_highest = A_list[-1]
            
        else:
            A_list.append(highest)
            break

    A_list = [int(A) for A in A_list]
    discounted_list = [int(B) for B in discounted_deque]
    print(sum(A_list)+sum(discounted_list))
else:
    A_list[-1] = A_list[-1]//(pow(2,M))
    print(A_list[-1])


### FIXED CODE ###

#141d
from collections import deque
import bisect
import math

N,M = map(int, input().split()) #1≤N,M≤10^5
A_list = list(map(int, input().split()))

#→高額なものに割引券を使った方が良い
if len(A_list) > 1:
    A_list.sort(reverse=False)
    highest = A_list.pop()
    next_highest = A_list[-1]

    discounted_deque = deque()

    while 1:
        use_tickets = math.ceil(math.log(highest/next_highest)/math.log(2))
        if use_tickets == 0:
            use_tickets = 1
        elif use_tickets > M:
            use_tickets = M
            
        highest /= pow(2,use_tickets)
        M -= use_tickets
        
        if M!= 0:
            discounted_deque.appendleft(highest)
            
            if len(A_list) > 0:
                if A_list[-1] > discounted_deque[-1]:
                    highest = A_list.pop()
                else:
                    highest = discounted_deque.pop()
            else:
                highest = discounted_deque.pop()
                
            if len(A_list) > 0 and len(discounted_deque) > 0:
                if A_list[-1] > discounted_deque[-1]:
                    next_highest = A_list[-1]
                else:
                    next_highest = discounted_deque[-1]
            elif len(A_list) == 0 and len(discounted_deque) > 0:
                next_highest = discounted_deque[-1]
            elif len(A_list) > 0 and len(discounted_deque) == 0:
                next_highest = A_list[-1]
            
        else:
            A_list.append(highest)
            break

    A_list = [int(A) for A in A_list]
    discounted_list = [int(B) for B in discounted_deque]
    
    print(sum(A_list)+sum(discounted_list))
else:
    A_list[-1] = A_list[-1]//(pow(2,M))
    print(A_list[-1])