Databases
StackOverflow2013
Postsdbo
PO
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO
    primarykey
    data
    text
    <p>Here's an implementation of the backtracking approach:</p> <pre><code>import java.util.Random; public class Sudoku { public static void main(String[] args) { Random rand = new Random(); int r = rand.nextInt(9); int c = rand.nextInt(9); int value = rand.nextInt(9) + 1; Board board = new Board(); board.set(r, c, value); System.out.println(board); solve(board, 0); System.out.println(board); } private static boolean solve(Board board, int at) { if (at == 9*9) return true; int r = at / 9; int c = at % 9; if (board.isSet(r, c)) return solve(board, at + 1); for (int value = 1; value &lt;= 9; value++) { if (board.canSet(r, c, value)) { board.set(r, c, value); if (solve(board, at + 1)) return true; board.unSet(r, c); } } return false; } static class Board { private int[][] board = new int[9][9]; private boolean[][] rs = new boolean[9][10]; private boolean[][] cs = new boolean[9][10]; private boolean[][][] bs = new boolean[3][3][10]; public Board() {} public boolean canSet(int r, int c, int value) { return !isSet(r, c) &amp;&amp; !rs[r][value] &amp;&amp; !cs[c][value] &amp;&amp; !bs[r/3][c/3][value]; } public boolean isSet(int r, int c) { return board[r][c] != 0; } public void set(int r, int c, int value) { if (!canSet(r, c, value)) throw new IllegalArgumentException(); board[r][c] = value; rs[r][value] = cs[c][value] = bs[r/3][c/3][value] = true; } public void unSet(int r, int c) { if (isSet(r, c)) { int value = board[r][c]; board[r][c] = 0; rs[r][value] = cs[c][value] = bs[r/3][c/3][value] = false; } } public String toString() { StringBuilder ret = new StringBuilder(); for (int r = 0; r &lt; 9; r++) { for (int c = 0; c &lt; 9; c++) ret.append(board[r][c]); ret.append("\n"); } return ret.toString(); } } } </code></pre>
    singulars
    1. This table or related slice is empty.
    1. POBrute force Algorithm for creation of Sudoku Board
      singulars
      1. PTQuestion
    1. PTAnswer
    1. USSheldon L. Cooper
    1. USSheldon L. Cooper
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    1. This table or related slice is empty.
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload