[Leetcode 36&37] Valid Sudoku & Sudoku Solver (Sudoku problem)

Title Link: Valid-sudoku

Import java.util.arrays;/** * Determine if a Sudoku is valid, according To:sudoku puzzles-the rules.the Sudoku Board Co Uld be partially filled, where empty cells is filled with the character '. A partially filled sudoku which is valid. Note:a Valid Sudoku board (partially filled) is not necessarily solvable. Only the filled cells need to be validated. * */public class Validsudoku {//number of solutions//every digit from 1 to 9 must appear:1-9 these nine numbers must appear only once in various cases//in each of the Colum NS, each column//in each of the rows,//and per row in every of the nine boxes. Nine Test//501/501 cases e:369 ms//submitted:1 minute ago//Check if the Sudoku is valid//Time complexity O (n^2) space complexity O (n) public boolean Isvalidsudoku (char[][] board) {BOOL  ean[] flag = new boolean[10];//mark//Check nine lines for (int i = 0; i < 9; i++) {Arrays.fill (flag, false); for (int j = 0; j < 9; J + +) {if (board[i][j] = = '. ') Continue;if (!flag[board[i][j]-' 0 ']) {flag[board[i][j]-' 0 '] = true;} else {return false;}}} Check nine columns for (int j = 0; J <9; J + +) {Arrays.fill (flag, false), for (int i = 0; i < 9; i++) {if (board[i][j] = = '. ')    Continue;if (!flag[board[i][j]-' 0 ']) {flag[board[i][j]-' 0 '] = true;} else {return false;}}} Check nine nine for (int i = 0; i < 9; i + = 3) {for (int j = 0; J < 9; J + = 3) {Arrays.fill (flag, false); for (int i1 = 0; I 1 < 3; i1++) {for (int j1 = 0; J1 < 3; j1++) {if (board[i + i1][j + j1] = = '. ')    Continue;if (!flag[board[i + i1][j + J1]-' 0 ']) {flag[board[i + i1][j + J1]-' 0 '] = true;} else {return false;}}}}    return true; }public static void Main (string[] args) {//TODO auto-generated method stub}}

Title Link: sudoku-solver

/** * Write A program to solve a Sudoku puzzle by filling the empty cells. Empty cells is indicated by the character '. Assume that there would be is only one unique solution. * */public class SudokuSolver {//6/6 test Cases passed.//status:accepted//runtime:260 ms//submitted:0 minutes ago//input    Sudoku only unique solution//backtracking//Time complexity O (n^4) space complexity O (1) public void Solvesudoku (char[][] board) {SOLVESUDOKU1 (board); public boolean solveSudoku1 (char[][] board) {for (int i = 0, i < 9; i++) {for (int j = 0; J < 9; j+ +) {if (board[i][j] = = '. ') {for (int k = 1; k <= 9; k++) {Board[i][j] = (char) (' 0 ' + K); if (IsValid (board, I, J) && SOLVESUDOKU1 (board)) { return true;} else {board[i][j] = '. ';    /backtracking method}}return false;}}}    return true; } public boolean isValid (char[][] board, int i, int j) {//Check the owning row for (int k = 0; k < 9; k++) {if (i! = k && Amp    BOARD[I][J] = = Board[k][j]) return false;} Check the owning column for (int k = 0; k < 9; k++) {if (j! = k && BOARD[I][J] = = Board[i][k]) return false;} Check the owning nine lattice for (int i1 = 3 * (I/3), I1 < (I/3 + 1) * 3; I1 + +) {for (int j1 = 3 * (J/3); J1 < (J/3 + 1) * 3; J 1 + +) {if (I1! = && J1! = J && board[i][j] = = Board[i1][j1]) return false;}    return true; } public static void Main (string[] args) {//TODO auto-generated method stub}}

[Leetcode 36&37] Valid Sudoku & Sudoku Solver (Sudoku problem)