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

d = {}
for i, a in enumerate(A):
    if a not in d:
        d[a] = []
    d[a].append(i)

dp = [[int(2e9)] * N for _ in range(Q + 1)]

dp[0][0] = 0
prv = -1
for i in range(Q):
    b = B[i]
    if i == 0:
        for j in d[b]:
            dp[i + 1][j] = min(dp[i + 1][j], dp[i][0] + j)
    else:
        for j in d[prv]:
            for k in d[b]:
                dp[i + 1][k] = min(dp[i + 1][k], dp[i][j] + abs(j - k))
    prv = b

mi = 2e9
for i in d[prv]:
    mi = min(mi, dp[Q][i])
print(mi)