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 C (GCC 5.4.1) (judge verdict: Runtime Error)

#include <stdio.h>
int main(void)
{
	int a=0,b=0,i=0,N=0,M=0,X=0,SUM=0;

	scanf("%d %d",&N,&M);
  
  	int A[N];
  
  	for(i=0;i<N;i++)
    {
  		scanf("%d",&a);
      	A[i]=a;
      
      	SUM+=a;
    }
  
  	X=SUM/(4*M);
  
  	a=0;
  
  	for(i=0;i<N;i++)
    {
      	a=A[i];
      
      	if(a>=X)
        {
        	b++;
        }
    }
  
  	if(b>=M)
    {
    printf("Yes");
    }
  
  	if(b<M)
    {
    printf("No");
    }
  
  	return 0;

}