#!/usr/bin/ python3.8
import sys
read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines
from bisect import bisect_left
import itertools

N, K = map(int, readline().split())
P = [0] + list(map(int, readline().split()))
B = [0] + list(map(int, readline().split()))

if K == 0:
    print(0)
    exit()

D = [sum(abs(x - y) for x, y in zip(P, B))]
for _ in range(K - 1):
    diff = 0
    Q = []
    while P[-2] > P[-1]:
        x = P.pop()
        diff -= abs(x - B[len(P)])
        Q.append(x)
    x = P.pop()
    diff -= abs(x - B[len(P)])
    Q.append(x)
    if not P[-1]:
        P = list(range(N + 1))
        D.append(sum(abs(x - y) for x, y in zip(P, B)))
        continue
    p = P.pop()
    diff -= abs(p - B[len(P)])
    n = bisect_left(Q, p)
    for x in itertools.chain([Q[n]], Q[:n], [p], Q[n + 1:]):
        diff += abs(x - B[len(P)])
        P.append(x)
    D.append(D[-1] + diff)
print(sum(D))