mod = 1000000007
eps = 10**-9


def main():
    import sys
    input = sys.stdin.readline

    N, K = map(int, input().split())
    A = list(map(int, input().split()))

    if K == 0:
        ans1 = ans2 = 0
        for a in A[1:]:
            ans1 += A[0] - a
        for a in A[:-1]:
            ans2 -= A[-1] - a
        print(min(ans1, ans2))
        exit()

    cs = [0] * (N+1)
    for i, a in enumerate(A):
        cs[i+1] = cs[i] + a

    def calc(i, l, r):
        a = A[i]
        return cs[l] - a * l + a * (i-l) - (cs[i] - cs[l]) + (cs[N-r] - cs[i+1]) - a * (K - (i-l) - 1) + a * r - (cs[-1] - cs[N-r])

    l = 0
    r = N - K
    ans = float("inf")
    for _ in range(N-K+1):
        il = l
        ir = N-1-r
        while ir - il > 2:
            mid_l = (il * 2 + ir) // 3
            mid_r = (il + ir * 2) // 3
            val_l = calc(mid_l, l, r)
            val_r = calc(mid_r, l, r)
            if val_l < val_r:
                ir = mid_r
            else:
                il = mid_l
        ans = min(ans, calc(il, l, r), calc(ir, l, r), calc((il+ir) // 2, l, r))
        l += 1
        r -= 1
    print(ans)


if __name__ == '__main__':
    main()