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++14 (GCC 5.4.1) (judge verdict: Runtime Error)

#include<bits/stdc++.h>
using namespace std;

#define pb push_back
#define ff first
#define ss second
#define N 200005
#define mod 1000000007
#define fo(n) for(int i=1;i<=n;i++)
typedef pair<int,int> pii;
typedef long long int ll;
typedef long int li;
int mod1 = 998244353;

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0); cout.tie(0);
    
    int n,k;
    cin>>n>>k;
    n = n%k;
    cout<<min(n,k-n);
}