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 main():
    take = input().split()
    number = int(take[0])
    num_negative = 0
    changes = int(take[1])
    lst = input().split()
    first_pos = 0
    for i in range(len(lst)):
        lst[i] = int(lst[i])
        if lst[i] < 0:
            if changes != 0:
                lst[i] = -1 * lst[i]
                changes -= 1
            num_negative += 1
        elif lst[i] == 0:
            changes = 0
            break
    summation = 0
    if changes != 0:
        if changes % 2 == 0:
            for num in lst:
                summation += num
            print(summation)
        else:
            lst[0] = -1 * lst[0]
            for num in lst:
                summation += num
            print(summation)
    else:
        for num in lst:
            summation += num
        print(summation)


main()
