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 = sc.nextLong();
long b = sc.nextLong();
long x = sc.nextLong();
long ax;
if(a != 0){
ax = ((a -1) / x )+ 1;
}else{
ax = 0;
}
long bx = b / x + 1;
long ans = bx - ax;

/*if(ans == 0&&a % x == 0){
ans = 1;
}*/

System.out.println(ans);


}
}