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(){
    unsigned long int a,b,c,d;
    unsigned long int num=0;
    scanf("%ld %ld %ld %ld",&a,&b,&c,&d);
    for (int i = a; i < b + 1; i++)
    {
        /* code */
        if (((i % c) == 0) || ((i % d) == 0))
        {
            /* code */
        }
        else
        {
            num = num + 1;
        }
        
    }
    printf("%ld\n",num);
}