Given a string, extract the first letter of each word in it. “Words” are defined as contiguous strings of alphabetic characters i.e. any upper or lower case characters a-z or A-Z. Examples:
Input : Geeks for geeks Output :Gfg Input : United Kingdom Output : UK
Below is the Regular expression to extract the first letter of each word. It uses ‘/b'(one of boundary matchers). Please refer How to write Regular Expressions? to learn it.
\b[a-zA-Z]
Java
// Java program to demonstrate extracting first // letter of each word using Regex import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class Test {
static void printFirst(String s)
{
Pattern p = Pattern.compile( "\\b[a-zA-Z]" );
Matcher m = p.matcher(s);
while (m.find())
System.out.print(m.group());
System.out.println();
}
public static void main(String[] args)
{
String s1 = "Geeks for Geeks" ;
String s2 = "A Computer Science Portal for Geeks" ;
printFirst(s1);
printFirst(s2);
}
} |
Output
GfG ACSPfG