From: Peter Hickman <peter@...>
Date: 2006-07-28T22:46:10+09:00
Subject: Re: For performance, write it in C - Part 2, comparing C, Ruby and Java

pat eyler wrote:
> Was the code for the Java and Ruby versions posted somewhere in
> the other thread?  (I must admit, I tuned a lot of that thread out 
> once it
> became a shouting match about the relative speeds of C and Java.)
>

The Ruby version was posted in the previous thread by Simon. I didn't 
post the Java version because, code wise, it is pretty much a line for 
line translation of the C version. But so you can see what the code was 
like here is the 3 x 3 version. The 5 x 5 version is just too damn big 
for a post, being as it is 5449 lines long!

public class Latin {
  private static int WidthOfBoard = 3;

  private static int NumberOfPermutations = 6;

  private static String[] OutputStrings = {
    "321",
    "231",
    "213",
    "312",
    "132",
    "123"
  };

  private static boolean[][] Compared = new boolean[6][6];

  private static int work[] = { 0, 0, 0 };

  private static void addARow(int row) {
    if (row == WidthOfBoard) {
      for (int x = 0; x < WidthOfBoard; x++) {
        if (x == 0) {
          System.out.print(OutputStrings[work[x]]);
        } else {
          System.out.print(":" + OutputStrings[work[x]]);
        }
      }
      System.out.println();
    } else {
      for (int x = 0; x < NumberOfPermutations; x++) {
        work[row] = x;

        boolean is_ok = true;
        if (row != 0) {
          for (int y = 0; y < row; y++) {
            if (Compared[work[row]][work[y]] != true) {
              is_ok = false;
              break;
            }
          }
        }
        if (is_ok == true) {
          addARow(row + 1);
        }
      }
    }
  }

  public static void main(String[] args) {
    // This nonsense is to get around the fact that Java will not allow
    // me to initialise an array in the declaration.

    Compared[0][2] = true;
    Compared[0][4] = true;
    Compared[1][3] = true;
    Compared[1][5] = true;
    Compared[2][0] = true;
    Compared[2][4] = true;
    Compared[3][1] = true;
    Compared[3][5] = true;
    Compared[4][0] = true;
    Compared[4][2] = true;
    Compared[5][1] = true;
    Compared[5][3] = true;

    addARow(0);
  }
}