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: Time Limit Exceeded)

// Anti-Division
#include<stdio.h>
int main(){
    int cnt = 0,sho_ci,sho_di;
    float A,B,C,D,sho_c,sho_d,sa_c,sa_d;

    scanf("%f%f%f%f",&A,&B,&C,&D);
    for(int i = A; i<= B; i++){
        sho_c =(float)(i / C);
        sho_ci = i / C;
        sho_d = (float)(i / D);
        sho_di = i / D;
        sa_c = (float)sho_c - sho_ci;
        sa_d = (float)sho_d - sho_di;
        // printf("i:%d sho_c:%f sho_ci:%d sho_d:%f sho_di:%d sa_c:%f sa_d:%f\n",i,sho_c,sho_ci,sho_d,sho_di,sa_c,sa_d);
        if((sa_c != 0)&&(sa_d != 0)){
            cnt++;
        }
    }
    printf("%d\n",cnt);
    return 0;
}