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 handle(nums, hs):
	tmp = nums.sort()
	if(hs&1):
		tmp[0] *= (-1)
		return sum(tmp)
	else:
		return sum(tmp)
		
if __name__ == '__main__':
	n, k = map(int, input().split())
	nums =list(map(int, input().split()))  
	pos = 0 
	for i in range(len(nums)):
		if(nums[i] < 0 ):
			pos = i 
		else:
			break
	if(pos == 0 and nums[0] >= 0 ):
		
		print(handle(nums, k ))
		exit()
	if(  pos + 1 >= k  ):
		for i in range(k):
			nums[i] = nums[i] * (-1)
		print(sum(nums))
		exit()
	if(pos + 1 < k):
		for i in range(k):
			nums[i] = nums[i] * (-1)
		print(handle(nums, pos + 1 - k))
		exit()