import sys

sys.setrecursionlimit(10**7)
def I(): return int(sys.stdin.readline().rstrip())
def MI(): return map(int,sys.stdin.readline().rstrip().split())
def LI(): return list(map(int,sys.stdin.readline().rstrip().split()))
def LI2(): return list(map(int,sys.stdin.readline().rstrip()))
def S(): return sys.stdin.readline().rstrip()
def LS(): return list(sys.stdin.readline().rstrip().split())
def LS2(): return list(sys.stdin.readline().rstrip())


N,K = MI()
A = LI()

ans0 = 0
for i in range(K):
    ans0 += abs(A[i]-A[0])

for i in range(K,N):
    ans0 -= abs(A[i]-A[0])

ans1 = 0
for i in range(N-1,N-K-1,-1):
    ans1 += abs(A[i]-A[0])
for i in range(N-K-1,-1,-1):
    ans1 -= abs(A[i]-A[0])

print(min(ans0,ans1))