Given any integer x, Aoki can do the operation below.
Operation: Replace x with the absolute difference of x and K.
You are given the initial value of an integer N. Find the minimum possible value taken by N after Aoki does the operation zero or more times.

-----Constraints-----
- 0 ≤ N ≤ 10^{18}
- 1 ≤ K ≤ 10^{18}
- All values in input are integers.

-----Input-----
Input is given from Standard Input in the following format:
N K

-----Output-----
Print the minimum possible value taken by N after Aoki does the operation zero or more times.

-----Sample Input-----
7 4

-----Sample Output-----
1

Initially, N=7.
After one operation, N becomes |7-4| = 3.
After two operations, N becomes |3-4| = 1, which is the minimum value taken by N.

见题面

见题面