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 C (GCC 5.4.1) (judge verdict: Wrong Answer)

#include<stdio.h>
 
int main(){
  long i, count = 0;
  long a, b, c, d;
  
  scanf("%ld %ld %ld %ld", &a, &b, &c, &d);
  
  for(i = a; i <= b; i++){
    if( i%c == 0 ){
      continue;
    }
    if( i%d != 0 ){
      continue;
    }
    count++;
  }
  
  printf("%d", count);
  
  return 0;
}