Problem:
Score : 300 points

Problem Statement

You are given four integers A, B, C, and D. Find the number of integers between A and B (inclusive) that can be evenly divided by neither C nor D.

Constraints

1\leq A\leq B\leq 10^{18}

1\leq C,D\leq 10^9

All values in input are integers.

Input

Input is given from Standard Input in the following format:

A B C D

Output

Print the number of integers between A and B (inclusive) that can be evenly divided by neither C nor D.

Sample Input 1

4 9 2 3

Sample Output 1

2

5 and 7 satisfy the condition.

Sample Input 2

10 40 6 8

Sample Output 2

23

Sample Input 3

314159265358979323 846264338327950288 419716939 937510582

Sample Output 3

532105071133627368

Solution in Java7 (OpenJDK 1.7.0) (judge verdict: Runtime Error)

import java.util.*;
public class Main {
  static int num=0;
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		// 整数の入力
		int A = sc.nextInt();
		int B=sc.nextInt();
      int C =sc.nextInt();
      int D=sc.nextInt();
      for(int i=A+1;i<B;i++){
      if(i%C==0||i%D==0){
        num++;
      }
      }
      System.out.println(num);
     	}
}