import java.util.*;

class StringExample {
        public static void main(String[] args) {
        String s1="Java";
        String s2="Programming";
        StringBuffer buffer=new StringBuffer();
        buffer.append(s1);
        buffer.append(s2);
        System.out.println(buffer.toString());
        String reversest = new StringBuffer(s1).reverse().toString();
        System.out.println("Reversed string1: "+reversest);
        int len1=s1.length();
        int len2=s2.length();
        System.out.println("Length of string 1= "+len1+" and string 2= "+len2);
        String repString=s1.replace(s1,"Simple");
        System.out.println(repString);
        String s3=s2.substring(0,6);
        System.out.println(s3);
        }
}