class output 
    {
        public static void main(String args[])
        {
            String a = "hello i love java";
            System.out.println(a.indexOf('e')+" "+a.indexOf('a')+" "+a.lastIndexOf('l')+" "+a.lastIndexOf('v'));
        }
    }

    class output 
    {
        public static void main(String args[])
        { 
             StringBuffer c = new StringBuffer("Hello");
             c.delete(0,2);
             System.out.println(c);
        }
    }

StringBuffer s1 = "one";
StringBuffer s2 = s1.append("two")

    class output 
    {
        public static void main(String args[])
        { 
             StringBuffer c = new StringBuffer("Hello");
             System.out.println(c.length());
        }
    }

  class output 
  {  
      public static void main(String args[]) 
      {  
          StringBuffer sb=new StringBuffer("Hello");  
          sb.replace(1,3,"Java");  
          System.out.println(sb);
      }  
  }

    class output 
    {
        public static void main(String args[])
        {
            char c[]={'a', '1', 'b' ,' ' ,'A' , '0'};
            for (int i = 0; i < 5; ++i)
            {
                   if(Character.isDigit(c[i]))
                       System.out.println(c[i]+" is a digit");
                   if(Character.isWhitespace(c[i]))
                       System.out.println(c[i]+" is a Whitespace character");
                   if(Character.isUpperCase(c[i]))
                       System.out.println(c[i]+" is an Upper case Letter");
                   if(Character.isLowerCase(c[i]))
                       System.out.println(c[i]+" is a lower case Letter");
               i=i+3;
            }
        }
    }