Java数独生成器无法正常工作
我一直在研究java中的数独谜题生成器，我写了这个类来生成谜题，但它没有正确生成谜题。 这是我得到的一个例子：
如您所见，这不是一个有效的数独解决方案。 但是看看我的代码，我不明白它为什么没有产生有效的谜题。 有人可以解释为什么这不能正常工作？
package sudoku; import java.util.Random; public class Puzzle { // number generator Random gen = new Random(); // 9x9 puzzle int puzzle[][] = new int[9][9]; public int[][] generate() { // add each number to the board for (int x = 0; x < 9; x++) { for (int y = 0; y < 9; y++) { boolean isValid = false; // keep generating new numbers until a valid number is found while (isValid == false) { // generate random number 1-9 int num = gen.nextInt(9) + 1; // check if number is valid if (checkRow(num, x) == true || checkCol(num, y) == true || checkSection(num, x, y) == true) { // add number to the board puzzle[x][y] = num; // exit loop isValid = true; } } } } return puzzle; } // check each element of the row for num, if num is found return false private boolean checkRow(int num, int row) { boolean valid = true; for (int i = 0; i < 9; i++) { if (puzzle[row][i] == num) { valid = false; break; } } return valid; } // check each element of the column for num, if num is found return false private boolean checkCol(int num, int col) { boolean valid = true; for (int i = 0; i < 9; i++) { if (puzzle[i][col] == num) { valid = false; break; } } return valid; } // check each element of the section for num, if num is found return false private boolean checkSection(int num, int xPos, int yPos) { int[][] section = new int[3][3]; section = getSection(xPos, yPos); boolean valid = true; for (int i = 0; i < 3; i++) { for (int j = 0; j < 3; j++) { if (section[i][j] == num) { valid = false; break; } } } return valid; } // return the 3x3 section the given coordinates are in private int[][] getSection(int xPos, int yPos) { int xIndex = 0; int yIndex = 0; int[][] section = new int[3][3]; // get x index if (xPos == 0 || xPos == 3 || xPos == 6) { xIndex = xPos; } else if (xPos == 1 || xPos == 4 || xPos == 7) { xIndex = xPos - 1; } else if (xPos == 2 || xPos == 5 || xPos == 8) { xIndex = xPos - 2; } // get y index if (yPos == 0 || yPos == 3 || yPos == 6) { yIndex = yPos; } else if (yPos == 1 || yPos == 4 || yPos == 7) { yIndex = yPos - 1; } else if (yPos == 2 || yPos == 5 || yPos == 8) { yIndex = yPos - 2; } int i = 0; int j = 0; // extract section from puzzle for (int x = xIndex; x < 3; x++) { for (int y = yIndex; y < 3; y++) { section[x][y] = puzzle[i][j]; i++; } j++; } return section; } } 行，列或部分有效是不够的。 他们都必须有效。 所以，改变这一行：
if (checkRow(num, x) == true || checkCol(num, y) == true || checkSection(num, x, y) == true)
同
if (checkRow(num, x) == true && checkCol(num, y) == true && checkSection(num, x, y) == true)
或者只是简单
if (checkRow(num, x) && checkCol(num, y) && checkSection(num, x, y)) {
可能还有其他错误，但这一行显然是错误的：
if (checkRow(num, x) == true || checkCol(num, y) == true || checkSection(num, x, y) == true) {
你应该在这里使用&& （布尔AND）而不是|| （布尔OR）。