from itertools import accumulate
N = int(input())
A = list(map(int, input().split()))
U = 10 ** 4 + 10

dp = [i for i in range(U)]
for a in A:
    dp = list(accumulate(dp, func=min))
    dp = [x + abs(i - a) for i, x in enumerate(dp)]
print(min(dp))