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.
import math


def main_function():
      n, k = [int(i) for i in input().split(" ")]
      a = sorted([int(i) for i in input().split(" ")])
      negatives = 0
      zeros = 0
      index = 0
      for i in a:
            if i < 0:
                  negatives += 1
            elif i == 0:
                  zeros += 1
      for i in range(k):
            if negatives > 0:
                  a[index] = -a[index]
                  index += 1
                  negatives -= 1
                  if negatives == 0:
                        a = sorted(a)
            else:
                  if zeros > 0:
                        break
                  else:
                        a[0] = -a[0]
      print(sum(a))











main_function()