n, k = map(int, input().split())
A = list(map(int, input().split()))

med = n // 2
Am1 = A[med]
Am2 = A[med - 1]
A0 = [abs(a - Am2) for a in A]
A0.sort()
A1 = [abs(a - Am1) for a in A]
A1.sort()
A2 = [abs(a - A[0]) for a in A]
A2.sort()
A3 = [abs(a - A[-1]) for a in A]
A3.sort()
ans0 = sum(A0[:k]) - sum(A0[k:])
ans1 = sum(A1[:k]) - sum(A1[k:])
ans2 = sum(A2[:k]) - sum(A2[k:])
ans3 = sum(A3[:k]) - sum(A3[k:])
print(min(ans0, ans1, ans2, ans3))