import java.io.*;

class UseCharListsA5
{
// Shows destructive append and change on lists
// using iteration

 public static void main(String[] args) throws IOException
 {
  BufferedReader in = new BufferedReader(
                        new InputStreamReader(System.in));
  CharListA L1=null,L2=null;
  char ch1,ch2;
  try {
       System.out.print("Enter first list of characters: ");
       L1 = CharListAIO.read(in);
       System.out.print("Enter second list of characters: ");
       L2 = CharListAIO.read(in);
      }
  catch(ListFormatException e)
      {
       System.out.println("Error: "+e.getMessage());
      }
  System.out.print("The lists are: ");
  CharListAIO.print(L1);
  System.out.print(" and ");
  CharListAIO.print(L2);
  System.out.println();
  System.out.println("Call destructive append ");
  destAppend(L1,L2);
  System.out.print("The lists are now: ");
  CharListAIO.print(L1);
  System.out.print(" and ");
  CharListAIO.print(L2);
  System.out.println();
  System.out.print("Enter first character: ");
  ch1=in.readLine().charAt(0);
  System.out.print("Enter second character: ");
  ch2=in.readLine().charAt(0);
  System.out.print("Call destructive change of first to ");
  System.out.println("second character");
  System.out.println("in second list ");
  destChange(ch1,ch2,L2);
  System.out.print("The lists are now: ");
  CharListAIO.print(L1);
  System.out.print(" and ");
  CharListAIO.print(L2);
  System.out.println();
 }

 public static void destAppend(CharListA L1,CharListA L2)
 {
  CharListA ptr;
  for(ptr=L1; ptr.tail!=null; ptr=ptr.tail);
  ptr.tail=L2;
 }

 public static void destChange(char ch1,char ch2,CharListA L)
 {
  for(CharListA ptr=L; ptr!=null; ptr=ptr.tail)
     if(ptr.head==ch1)
        ptr.head=ch2;
 }

}