revese.java

//StringBuilder vs String

//quadratic time
public static String reverse(String s)
{
   String rev = "";
   for (int i=s.length();i>=0;i--) {
       rev += s[i];
   }
   return rev;
}


//Linear time
public static String reverse(String s)
{
   StringBuilder rev = new StringBuilder ();
   for (int i=s.length();i>=0;i--) {
       rev.append(s[i]);
   }
   return rev;
}