
n = int(input())

arr = list()
arr = (input().split(' '))

arr = sorted(arr)

temp1 = 0
temp2 = 0

for i in range(0,int(n/2)):
    temp1 = temp1 + abs(int(arr[i])-(2*i+1))
    temp2 = temp2 + abs(int(arr[i])-(2*i+2))
print(min(temp1,temp2))


