Problem: Iahub and his friend Floyd have started painting a wall. Iahub is painting the wall red and Floyd is painting it pink. You can consider the wall being made of a very large number of bricks, numbered 1, 2, 3 and so on. 

Iahub has the following scheme of painting: he skips x - 1 consecutive bricks, then he paints the x-th one. That is, he'll paint bricks x, 2·x, 3·x and so on red. Similarly, Floyd skips y - 1 consecutive bricks, then he paints the y-th one. Hence he'll paint bricks y, 2·y, 3·y and so on pink.

After painting the wall all day, the boys observed that some bricks are painted both red and pink. Iahub has a lucky number a and Floyd has a lucky number b. Boys wonder how many bricks numbered no less than a and no greater than b are painted both red and pink. This is exactly your task: compute and print the answer to the question. 

Input

The input will have a single line containing four integers in this order: x, y, a, b. (1 ≤ x, y ≤ 1000, 1 ≤ a, b ≤ 2·109, a ≤ b).

Output

Output a single integer — the number of bricks numbered no less than a and no greater than b that are painted both red and pink.

Examples

Input

2 3 6 18


Output

3

Note

Let's look at the bricks from a to b (a = 6, b = 18). The bricks colored in red are numbered 6, 8, 10, 12, 14, 16, 18. The bricks colored in pink are numbered 6, 9, 12, 15, 18. The bricks colored in both red and pink are numbered with 6, 12 and 18. 

Solution (in JAVA):

Solution:
/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */

import java.io.*;
import java.math.BigInteger;
import java.util.*;
import java.text.*;

public class cf340a {
    
    static BufferedReader br;
    static Scanner sc;
    static PrintWriter out;
    
    public static void initA() {
        try {
            br = new BufferedReader(new InputStreamReader(System.in));
            sc = new Scanner(System.in);
            out = new PrintWriter(System.out);
        } catch (Exception e) {
        }
    }

    static boolean next_permutation(Integer[] p) {
        for (int a = p.length - 2; a >= 0; --a) {
            if (p[a] < p[a + 1]) {
                for (int b = p.length - 1;; --b) {
                    if (p[b] > p[a]) {
                        int t = p[a];
                        p[a] = p[b];
                        p[b] = t;
                        for (++a, b = p.length - 1; a < b; ++a, --b) {
                            t = p[a];
                            p[a] = p[b];
                            p[b] = t;
                        }
                        return true;
                    }
                }
            }
        }
        return false;
    }
    
    public static String getString() {
        try {
            return br.readLine();
        } catch (Exception e) {
        }
        return "";
    }
    
    public static Integer getInt() {
        try {
            return Integer.parseInt(br.readLine());
        } catch (Exception e) {
        }
        return 0;
    }
    
    public static Integer[] getIntArr() {
        try {
            StringTokenizer temp = new StringTokenizer(br.readLine());
            int n = temp.countTokens();
            Integer temp2[] = new Integer[n];
            for (int i = 0; i < n; i++) {
                temp2[i] = Integer.parseInt(temp.nextToken());
            }
            return temp2;
        } catch (Exception e) {
        }
        return null;
    }
    
    public static Long[] getLongArr() {
        try {
            StringTokenizer temp = new StringTokenizer(br.readLine());
            int n = temp.countTokens();
            Long temp2[] = new Long[n];
            for (int i = 0; i < n; i++) {
                temp2[i] = Long.parseLong(temp.nextToken());
            }
            return temp2;
        } catch (Exception e) {
        }
        return null;
    }
    
    public static String[] getStringArr() {
        try {
            StringTokenizer temp = new StringTokenizer(br.readLine());
            int n = temp.countTokens();
            String temp2[] = new String[n];
            for (int i = 0; i < n; i++) {
                temp2[i] = (temp.nextToken());
            }
            return temp2;
        } catch (Exception e) {
        }
        return null;
    }
    
    public static void print(Object a) {
        out.println(a);
    }
    
    public static void print(String s, Object... a) {
        out.printf(s, a);
    }
    
    public static int nextInt() {
        return sc.nextInt();
    }
    
    public static double nextDouble() {
        return sc.nextDouble();
    }
    
    public static void main(String[] ar) {
        initA();
        solve();
        out.flush();
    }
    static long gcd(long a, long b){
        return BigInteger.valueOf(a).gcd(BigInteger.valueOf(b)).longValue();
    }
    
    public static void solve() {
        Long xx[] = getLongArr();
        long x = xx[0], y = xx[1], a= xx[2], b= xx[3];
        
        long kpk = (x*y)/gcd(x,y);
        long v = (b/kpk) - (a/kpk);
        //print("%d/%d=%d\n",b,kpk,b/kpk);
        if(a%kpk==0){
            v++;
        }
        print(v);
        
        
    }
}