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)

/* ABC131-C
   Yuta Takayanagi  */

#include<stdio.h>
int main(void){
    long long int a, b, count, i;
    int c, d;

    count = 0;

    scanf( "%I64d %I64d %d %d" , &a, &b, &c, &d);

    for(i=a; i <= b; i++){

        if(i%c!=0 && i%d!=0){

            count++;

        }

    }

    printf( "%I64d\n" , count);

    return 0;
}