Doubt related to regex

[Aditi Roychoudhury]

Hi All,

This is a question from K&B master exam

import java.util.regex.*;
class Regex2{
public static void main(String args []){
Pattern p = Pattern.compile(args[0]);
Matcher m = p.matcher(args[1]);
boolean b = false;
while (b = m.find()) {
System.out.println(m.start() + m.group() + "");
}
}
}


And the invocation java Regex2 "\d\s\w" "12s 4 w 33 1"

produces the output 44 w and 93 1

Now,since the 2 groups found are "4 w" and "3 1",i understand that the first part of the output is "44 w".
Along the same lines,the 2nd part of the output should have been "33 1".
can someone explain how is it "93 1"?

Thanks,
Aditi.

[Byju Joy]

System.out.println(m.start() + m.group() + "");

Is it because the start() index is also printed prefixing m.group()?

[Henry Wong]

Along the same lines,the 2nd part of the output should have been "33 1".
can someone explain how is it "93 1"?

Because "3 1" is at index location 9. My question is, why do you think it should be at index location 3?

Henry

[Aditi Roychoudhury]

Henry and Byju,

Thanks a lot for your answers.
I was thinking that the start() method returns the first element of the group.I was obviously wrong.Thanks again.

Thanks,
Aditi