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: Wrong Answer)



import java.util.*;

public class Main {
	//static boolean f;
	static long min;
	
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		
		/* 入力の受け取り
		 * String s = sc.next();
		 * int a = sc.nextInt();
		 * long a = sc.nextLong();
		 */
		
		// 文字列(String)を文字(char)に分解
		// char[] s_char = s.toCharArray();
		
		long n = sc.nextLong();
		long k = sc.nextLong();
		
		if(n == 0) 
			min = 0;
		else if(n >= k)
			min = n%k;
		else
			min = k-(n%k);
		
		System.out.println(min);
		
		/*
		 * if(f)
		 *	System.out.println("Yes");
		 * else
		 * 	System.out.println("No");
		 */
	}
}