Problem Statement

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.

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.

Constraints

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

Sample Input 1

7 4

Sample Output 1

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.

Sample Input 2

2 6

Sample Output 2

2

N=2 after zero operations is the minimum.

Sample Input 3

1000000000000000000 1

Sample Output 3

0

见题面 Input 部分

见题面 Output 部分