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,K,gcd,lcm,i;
    scanf("%lld%lld%lld%lld",&A,&B,&C,&D);
    for(i=1;i<=C && i<=D;i++)
    {
        if(C%i==0 && D%i==0)
        gcd=i;
    }
    lcm=(C*D)/gcd;
    K=(B-A+1)-((B-A+1)/C)-((B-A+1)/D)+((B-A+1)/lcm);
    printf("%d\n",K);
    return 0;

}