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() {
	int n,m,k=0,vote=0;
	int check;
	scanf("%d%d",&n,&m);
	int arr[n+1];
	for(int i=1;i<=n;i++)
	{
	    scanf("%d",&arr[i]);
	    vote=vote+arr[i];
	}
	if(vote%(4*m)==0)
	    check=vote/(4*m);
	else
	    check=(vote/(4*m))+1;
	for(int i=1;i<=n;i++)
	{
	    if(arr[i]>=check)
	    k++;
	}
	if(k>=m)
	    printf("YES");
	else
    	printf("NO");
	return 0;
}