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 copy

l = input().split()
n, k = int(l[0]), int(l[1])
arr = [0] + [int(x) for x in input().split()]

# ans = -float('inf')
#
#
# def sol(i, tmp):
#     global ans
#     if i == 0:
#         ans = max(ans, sum(tmp))
#         return
#
#     for j in range(n):
#         a_cp = copy.copy(tmp)
#         a_cp[j] *= -1
#         sol(i - 1, a_cp)
#
#
# sol(k, arr)
# print(ans)


dp = [[0 for _ in range(k+1)] for _ in range(n+1)]
dp[1][0] = arr[1]
for i in range(1, n+1):
    for j in range(1, k+1):
        # print(i)
        # print(i, arr[i])
        dp[i][j] = max(arr[i]*(-1) + dp[i-1][k-1], arr[i] + dp[i-1][k])
# print(dp)
print(dp[n][k])
