You are given nonnegative integers a and b (a ≤ b), and a positive integer x. Among the integers between a and b, inclusive, how many are divisible by x?

Constraints

* 0 ≤ a ≤ b ≤ 10^{18}
* 1 ≤ x ≤ 10^{18}

Input

The input is given from Standard Input in the following format:


a b x


Output

Print the number of the integers between a and b, inclusive, that are divisible by x.

Examples

Input

4 8 2


Output

3


Input

0 5 1


Output

6


Input

9 9 2


Output

0


Input

1 1000000000000000000 3


Output

333333333333333333
import java.util.*;

class Main{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        
        long a = Long.parseLong(sc.next());
        long b = Long.parseLong(sc.next());
        
        long x = Long.parseLong(sc.next());
        
        long ans = 0;
        ans = (b/x)-(a/x);
        if(a%x==0){
            ans++;
        }
        
        System.out.println(ans);
    }
}