n = int(input())
y = list(map(int, input().split()))
INF = 10 ** 9

ans = 10 ** 18
dp = [[INF] * (10 ** 4 + 1) for i in range(n + 1)]
dp[0][0] = 0

for i in range(n):
    ru = [INF] * (10 ** 4 + 2)
    for height in range(10 ** 4 + 1):
        ru[height + 1] = min(ru[height], dp[i][height])
    for height in range(10 ** 4 + 1):  
        dp[i + 1][height] = ru[height + 1] + abs(height - y[i])

print(min(dp[-1]))