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:
import java.io.File;import java.io.FileInputStream;import java.io.FileNotFoundException;
import java.io.IOException;import java.io.InputStream;import java.io.PrintWriter;
import java.security.AccessControlException;import java.util.List;public class _p000340A {
static public void main(final String[] args) throws IOException{p000340A._main(args);}

static class p000340A extends Solver{public p000340A(){singleTest=true;}@Override public 
void solve()throws IOException{int x=sc.nextInt();int y=sc.nextInt();int a=sc.nextInt();
int b=sc.nextInt();sc.nextLine();int g=GreatestCommonFactor.apply(x,y);int f=x/g
*y;int res=b/f-(a-1)/f;pw.println(res);}static public void _main(String[]args)throws 
IOException{new p000340A().run();}}static class GreatestCommonFactor{public static 
int apply(int a,int b){int max=Math.max(a,b);int min=Math.min(a,b);while(min>1){
int r=max%min;if(r==0){return min;}max=min;min=r;}return 1;}public static long apply(long 
a,long b){long max=Math.max(a,b);long min=Math.min(a,b);while(min>1){long r=max%
min;if(r==0){return min;}max=min;min=r;}return 1;}}static class MyScanner{private 
StringBuilder cache=new StringBuilder();int cache_pos=0;private int first_linebreak
=-1;private int second_linebreak=-1;private StringBuilder sb=new StringBuilder();
private InputStream is=null;public MyScanner(final InputStream is){this.is=is;}public 
String charToString(final int c){return String.format("'%s'",c=='\n'?"\\n":(c=='\r'
?"\\r":String.valueOf((char)c)));}public int get(){int res=-1;if(cache_pos<cache.length())
{res=cache.charAt(cache_pos);cache_pos++;if(cache_pos==cache.length()){cache.delete(0,
cache_pos);cache_pos=0;}}else{try{res=is.read();}catch(IOException ex){throw new 
RuntimeException(ex);}}return res;}private void unget(final int c){if(cache_pos==
0){cache.insert(0,(char)c);}else{cache_pos--;}}public String nextLine(){sb.delete(0,
sb.length());int c;boolean done=false;boolean end=false;while((c=get())!=-1){if(check_linebreak(c))
{done=true;if(c==first_linebreak){if(!end){end=true;}else{cache.append((char)c);
break;}}else if(second_linebreak!=-1 && c==second_linebreak){break;}}if(end && c
!=first_linebreak && c!=second_linebreak){cache.append((char)c);break;}if(!done)
{sb.append((char)c);}}return sb.toString();}private boolean check_linebreak(int 
c){if(c=='\n'|| c=='\r'){if(first_linebreak==-1){first_linebreak=c;}else if(c!=first_linebreak 
&& second_linebreak==-1){second_linebreak=c;}return true;}return false;}public int 
nextInt(){return Integer.parseInt(next());}public long nextLong(){return Long.parseLong(next());
}public boolean hasNext(){boolean res=false;int c;while((c=get())!=-1){if(!check_linebreak(c)
&& c!=' '&& c!='\t'){res=true;unget(c);break;}}return res;}public String next(){
sb.delete(0,sb.length());boolean started=false;int c;while((c=get())!=-1){if(check_linebreak(c)
|| c==' '|| c=='\t'){if(started){unget(c);break;}}else{started=true;sb.append((char)c);
}}return sb.toString();}public int nextChar(){return get();}public boolean eof()
{int c=get();boolean res=false;if(c!=-1){unget(c);}else{res=true;}return res;}public 
double nextDouble(){return Double.parseDouble(next());}}static abstract class Solver
{protected String nameIn=null;protected String nameOut=null;protected boolean singleTest
=false;protected MyScanner sc=null;protected PrintWriter pw=null;private int current_test
=0;private int count_tests=0;protected int currentTest(){return current_test;}protected 
int countTests(){return count_tests;}private void process()throws IOException{if(!singleTest)
{count_tests=sc.nextInt();sc.nextLine();for(current_test=1;current_test<=count_tests;
current_test++){solve();pw.flush();}}else{count_tests=1;current_test=1;solve();}
}abstract protected void solve()throws IOException;public void run()throws IOException
{boolean done=false;try{if(nameIn!=null){if(new File(nameIn).exists()){try(FileInputStream 
fis=new FileInputStream(nameIn);PrintWriter pw0=select_output();){select_output();
done=true;sc=new MyScanner(fis);pw=pw0;process();}}else{throw new RuntimeException("File "
+new File(nameIn).getAbsolutePath()+" does not exist!");}}}catch(IOException | AccessControlException 
ex){}if(!done){try(PrintWriter pw0=select_output();){sc=new MyScanner(System.in);
pw=pw0;process();}}}private PrintWriter select_output()throws FileNotFoundException
{if(nameOut!=null){return new PrintWriter(nameOut);}return new PrintWriter(System.out);
}}static abstract class Tester{static public int getRandomInt(final int min,final 
int max){return(min+(int)Math.floor(Math.random()*(max-min+1)));}static public long 
getRandomLong(final long min,final long max){return(min+(long)Math.floor(Math.random()
*(max-min+1)));}static public double getRandomDouble(final double min,final double 
maxExclusive){return(min+Math.random()*(maxExclusive-min));}abstract protected void 
testOutput(final List<String>output_data);abstract protected void generateInput();
abstract protected String inputDataToString();private boolean break_tester=false;
protected void beforeTesting(){}protected void breakTester(){break_tester=true;}
public boolean broken(){return break_tester;}}}