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.Scanner;
public class Main {
	public static void main(String[] args){
		Scanner stdIn=new Scanner(System.in);
		long a=stdIn.nextLong();
		long b=stdIn.nextLong();
		long x=stdIn.nextLong();
		long count=0;
		for(int i=0;i<=(b/x);i++){
			if((a<=x*i)&&(x*i<=b)){
			count++;
			count+=((b-x*i)/x);
			break;
		}
		}
		System.out.print(count);
	}
}