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) {

        long A;
        long B;
        long x;
        try (Scanner sc = new Scanner(System.in)) {
            A = sc.nextLong();
            B = sc.nextLong();
            x = sc.nextLong();
        }

        long ax = ((A - 1) >= 0) ? ((A - 1) / x) + 1 : 0;
        long bx = (B / x) + 1;

        System.out.println(bx - ax);
    }

}
