/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
import java.util.regex.*;
/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		String str; 
		Scanner sc=new Scanner(System.in).useDelimiter("[\r\n]+");
		System.out.println("Enter String");
		str=sc.next(); 
		Pattern pat = Pattern.compile("a\\sb"); 
		Matcher m = pat.matcher(str);
		if( m.find() ) {
			System.out.println("Success"); 
		}
		else {
				System.out.println("Failed"); 
		}
	}
}

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