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 (void){
int A,B,C,D,i,j,k,count=0;
scanf("%d",&A);
scanf("%d",&B);
scanf("%d",&C);
scanf("%d",&D);

for(i=0;i*C<=B;i++){
if(i*C>=A){
count++;
}
}
for(j=0;j*D<=B;j++){
if(j*D>=A){
count++;
}
}
for(k=0;k*D*C<=B;k++){
if(k*D*C>=A){
count--;
}
}
printf("%d",(B-A+1)-count);
return 0;
}