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 Java8 (OpenJDK 1.8.0) (judge verdict: Time Limit Exceeded)

import java.util.Scanner;
import java.lang.Math;
class Main{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        long n = sc.nextLong();
        long k = sc.nextLong();
        sc.close();

        while(n>=k){
            n = n-k;
        }
        // System.out.println(n);
        System.out.println(Math.min(n,Math.abs(k-n)));
        // n=Math.min(n,k-n);
        // System.out.println(n);
    }
        
    public static int[] sort(int[] a){
        int x;
        for(int i=0;i<a.length;i++){
            x = a[i];
            for(int j=0;j<a.length;j++){
                if(x == Math.max(x,a[j])){
                    a[i]=a[j];
                    a[j]=x;
                    x=a[i];
                }
            }
        }
        return a;
    }
}