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++14 (GCC 5.4.1) (judge verdict: Runtime Error)

#include <iostream>
#include <vector>
using namespace std ;
int main(){
    int a, b, c, d,  N, k;
    cin >> a >> b >> c >> d ;
    N = b - a + 1 ;
    vector<int> vec(N) ;
    //bからaまでの配列を作る
    for(int i = 0; i < b - a + 1; i++){
        vec.at(i) = a + i ;
    }
    //vec配列をcとdの余剰を求めて、１以上だったらkにカウントする
    for(int i = 0; i < b - a + 1; i++){
        if(vec.at(i) % c > 0 && vec.at(i) % d){
            k = k + 1 ;
        }
    }
    cout << k << endl ;

    return 0 ;

}