Roma works in a company that sells TVs. Now he has to prepare a report for the last year.

Roma has got a list of the company's incomes. The list is a sequence that consists of *n* integers. The total income of the company is the sum of all integers in sequence. Roma decided to perform exactly *k* changes of signs of several numbers in the sequence. He can also change the sign of a number one, two or more times.

The operation of changing a number's sign is the operation of multiplying this number by -1.

Help Roma perform the changes so as to make the total income of the company (the sum of numbers in the resulting sequence) maximum. Note that Roma should perform exactly *k* changes.
The first line contains two integers *n* and *k* (1 ≤ *n*, *k* ≤ 10<sup class="upper-index">5</sup>), showing, how many numbers are in the sequence and how many swaps are to be made.

The second line contains a non-decreasing sequence, consisting of *n* integers *a*<sub class="lower-index">*i*</sub> (|*a*<sub class="lower-index">*i*</sub>| ≤ 10<sup class="upper-index">4</sup>).

The numbers in the lines are separated by single spaces. Please note that the given sequence is sorted in non-decreasing order.
def mergeSort(myList):
    if len(myList) > 1:
        mid = len(myList) // 2
        left = myList[:mid]
        right = myList[mid:]
        mergeSort(left)
        mergeSort(right)
        i = 0
        j = 0
        k = 0
        while i < len(left) and j < len(right):
            if left[i] <= right[j]:
                myList[k] = left[i]
                i += 1
            else:
                myList[k] = right[j]
                j += 1
            k += 1
        while i < len(left):
            myList[k] = left[i]
            i += 1
            k += 1
        while j < len(right):
            myList[k] = right[j]
            j += 1
            k += 1
def check(a):
    for i in a:
        if i < 0 :
            return False
    return True
def pacc(a,count,k):
    while not check(a):
        if count == k:
            break
        mergeSort(a)
        a[0]*=-1
        count+=1
    return a,count
n,k = map(int,input().split())
a = list(map(int,input().split()))
count = 0
inp = list(pacc(a,count,k))
a = inp[0]
count = inp[1]
if count == k:
    print(sum(a))
else:
    while count != k:
        a[0] *=-1
        count+=1
    print(sum(a))