Problem:
Score : 300 points

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.

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 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

Solution in Java7 (OpenJDK 1.7.0) (judge verdict: Runtime Error)

    import java.util.*;
    class Main
    {
      public static void main(String args[])
      {
        Scanner sc=new Scanner (System.in);
        int a,b,t=0;
        a=sc.nextInt();
        b=sc.nextInt();
        while(a>b)
        {
          a=Math.abs(a-b);
          t++;
        }
        System.out.println(t);
      }
    }