/*************************************************************************/
//  This is a class that implements a two-dimensional matrix of characters.
//  Examples of uses include representing a maze or the state of a
//  game of Tic-Tac-Toe.
/*************************************************************************/

import java.io.*;
class CharMatrix implements CharMatrixInterface
{
    // Holds the entries of the two-dimensional character matrix ...
    private char [][] M;

    // Number of rows, columns in character matrix
    private int numRows, numColumns;

    /********************************************************************/
    //  Default constructor ...
    /********************************************************************/
    public CharMatrix()
    {
       M = null;
       numRows = numColumns = 0;
    }

    /********************************************************************/
    // Constructor that reads a character matrix from a file.  The file
    //  is a text file, and must be formatted as follows:
    //
    // - The first line of the file is an integer n that indicates the number
    //    of rows of the matrix;
    // - The second line of the file is an integer that indicates the number
    //    m of columns of the matrix;
    // - For each i from 3 to n+2, line i contains the characters for row
    //    i-3 of the matrix.  (The rows are numbered 0 through n-1 and the
    //    columns are numbered 0 through m-1.)  The line must contain exactly
    //    m characters, not counting the newline character.
    //
    // Example:
    // ------------
    // 3
    // 4
    // abcd
    // acdb
    // baad
    // ------------
    /********************************************************************/
    public CharMatrix(String filename) 
    {
       try
       { 
           BufferedReader inputStream =
             new BufferedReader(new FileReader(filename));
           String line = inputStream.readLine();
           line = line.trim();
           numRows = Integer.parseInt(line);   
           line = inputStream.readLine();
           numColumns = Integer.parseInt(line);

           M = new char [numRows][numColumns];
 
           for (int i = 0; i < numRows; i++)
           {
               line = inputStream.readLine();
               // line = line.trim();
               if (line.length() != numColumns)
               {
                   System.out.println("ERROR:  Line " + i + 
                                      " is not of the right length");
                   System.exit(1);
               }
               for (int j = 0; j < numColumns; j++)
                  setEntry(i,j,line.charAt(j)); 
           }
       }
       catch (FileNotFoundException e)
       {
           System.out.print("\n\n");
           System.out.println(e.getMessage());
           System.out.print("\n\n");
           System.exit(0);
       }
       catch(IOException e)
       {
           System.out.print("\n\n");
           System.out.println(e.getMessage());
           System.out.print("\n\n");
           System.exit(0);
       }
    }

    /**********************************************************************/
    // Get the number of rows of the matrix ...
    /**********************************************************************/
    public int getNumRows()
    {
       return numRows;
    }

    /**********************************************************************/
    // Get the number of columns of the matrix ...
    /**********************************************************************/
    public int getNumColumns()
    {
       return numColumns;
    }

    /**********************************************************************/
    // Get the entry in row i and column j ...
    /**********************************************************************/
    public char getEntry(int i, int j)
    {
       return M[i][j];
    }

    /**********************************************************************/
    // Change the value of the entry in row i and column j to newValue ..
    /**********************************************************************/
    public void setEntry(int i, int j, char newValue)
    {
       M[i][j] = newValue;
    }

    public String toString()
    {

       // Label the column numbers ...
       String Result = "  ";
       for (int i = 0; i < numColumns; i++)
           Result += (i % 10);
       Result += "\n";

       /* for (int i = -1; i <= numColumns; i++)
           Result += "-";     
       Result += "\n"; */

       for (int i = 0; i < numRows; i++)
       {
           Result += (i % 10 + "|");  // label with the row number

           for (int j = 0; j < numColumns; j++)
               Result += getEntry(i,j);
           Result += "\n";
       }

       /*Result += " ";
       for (int i = -1; i <= numColumns; i++)
           Result += "-";
       Result += "\n";*/
       return Result;
    }
}