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.*;
public class Main {
	private static Scanner sc;	 
	public static void main(String[] args) {
		sc = new Scanner(System.in);
		Long a = sc.nextLong();
		Long b = sc.nextLong();
		Long x = sc.nextLong();
		Long count ;
		Long sum1 = a/x;
		long sum2 = b/x;
		if(a%x==0)sum1=sum1-1;
		count = sum2-sum1;
		System.out.println(count);
		
	}

}
