/**
 * Test1
 * The program builds a two-dimensional array of characters
 * Input is pairs of strings where the first character of
 * the first input string is the character to be found and
 * the first character of the second input string is the one
 * to be substituted for the first
 *
 * Author: Beth Katz 
 * February 2008
 */

import java.io.*;
import java.util.*;

public class Test1 {
   public static void main(String[ ] args) {
      Scanner console = new Scanner(System.in);
      char [][] array = new char[][] {
         {'h','b','t','n','r','o','c','h'},
         {'a','o','e','h','a','n','r','k'},
         {'m','o','a','i','s','g','a','g'},
         {'i','t','i','v','p','c','n','i'},
         {'r','a','u','i','o','i','b','n'},
         {'g','t','e','r','f','i','e','d'},
         {'l','o','n','f','k','n','r','i'},
         {'i','p','u','m','g','e','r','a'},
         {'p','t','g','r','a','v','y','n'},
         {'s','q','u','a','s','h','a','m'}};
      char target, sub;   
      String input;

      print(array);
      System.out.println("\nEnter a char to find and a char to replace it with:");
      try {
         while(console.hasNext( )) {
            input = console.next( );
            target = input.charAt(0);
            input = console.next( );
            sub = input.charAt(0);
            System.out.println(replaceReport(array, target, sub));
                      print(array);
            System.out.println("\nEnter a char and its replacement:");
         }
      }
      catch (NoSuchElementException e) {
         System.out.println("Enter pairs of strings. Quitting.");
      }
   }

   /**
    * substitutes subCh for orig in array a and returns how many 
    * substitutions were made
    */
   public static int replace(char[][] a, char orig, char subCh) {
      int count = 0;
      for (int r = 0; r < a.length; r++) {
         for (int c = 0; c < a[r].length; c++) {
            if (a[r][c] == orig) {
               a[r][c] = subCh;
               count++;
            }
         }   
      }
      return count;
   }

   /**
    * substitutes subCh for orig in array a and reports on what happened
    */
   public static String replaceReport(char[][] a, char orig, char subCh) {
      int times = replace(a, orig, subCh);
      if (times == 0) {
         return "No replacements";
      } else {
         String answer = new String(times + " replacements");
         return (answer);
      }
   }
   
   /**
    * prints the array neatly
    */
   static void print(char[][] a) {
      for (int r = 0; r < a.length; r++) {
         for (int c = 0; c < a[r].length; c++) {
            System.out.print(a[r][c] + " ");
         }
         System.out.println( );
      }
   }
}