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 Python (3.4.3) (judge verdict: Wrong Answer)

a,b,c,d = map(int,input().split())
u = b - a + 1
import math
div_c = set()
div_d = set()
for i in range(1,int(math.sqrt(c))+1):
    if c % i == 0:
        div_c.add(i)
print(div_c)
for i in range(1,int(math.sqrt(d))+1):
    if d % i == 0:
        div_d.add(i)
print(div_d)
gcd = max(list(div_c & div_d))
cd = c*d/gcd    
n_c = b//c - (a-1)//c
n_d = b//d - (a-1)//d
n_cd = int(b//cd - (a-1)//cd)
print(u - n_c - n_d + n_cd)