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 long int a,b,c,d,f,max,l;
    scanf("%lld%lld%lld%lld",&a,&b,&c,&d);
    max = (c > d)? c : d;
    while(1)
    {
        if(max%c==0 && max%d==0)
         {
             l=max;
             break;
         }
        max++;
    }
    f=((b-a)+1)-(((b-a)/c)+1)-(((b-a)/d)+1)+(((b-a)/l)+1);
    printf("%lld",f);
}