36. Valid Sudoku
Determine if a 9x9 Sudoku board is valid. Only the filled cells need to be validated according to the following rules:
- Each row must contain the digits
1-9
without repetition. - Each column must contain the digits
1-9
without repetition. - Each of the 9
3x3
sub-boxes of the grid must contain the digits1-9
without repetition.
A partially filled sudoku which is valid.
The Sudoku board could be partially filled, where empty cells are filled with the character '.'
.
Example 1:
Input: [ ["5","3",".",".","7",".",".",".","."], ["6",".",".","1","9","5",".",".","."], [".","9","8",".",".",".",".","6","."], ["8",".",".",".","6",".",".",".","3"], ["4",".",".","8",".","3",".",".","1"], ["7",".",".",".","2",".",".",".","6"], [".","6",".",".",".",".","2","8","."], [".",".",".","4","1","9",".",".","5"], [".",".",".",".","8",".",".","7","9"] ] Output: true
Example 2:
Input: [ ["8","3",".",".","7",".",".",".","."], ["6",".",".","1","9","5",".",".","."], [".","9","8",".",".",".",".","6","."], ["8",".",".",".","6",".",".",".","3"], ["4",".",".","8",".","3",".",".","1"], ["7",".",".",".","2",".",".",".","6"], [".","6",".",".",".",".","2","8","."], [".",".",".","4","1","9",".",".","5"], [".",".",".",".","8",".",".","7","9"] ] Output: false Explanation: Same as Example 1, except with the 5 in the top left corner being modified to 8. Since there are two 8's in the top left 3x3 sub-box, it is invalid.
题意:每一行排列数字1-9且不能重复,每一列排列1-9且不能重复,每个3X3小方形排列1-9且不重复,验证是否数独
代码如下:
/** * @param {character[][]} board * @return {boolean} */ var isValidSudoku = function(board) { var len=board.length; if(len===0) return true; for(var i=0;i<len;i++){ var row=[]; var col=[]; for(var k=0;k<10;k++){ row[k]=false; col[k]=false; } for(var j=0;j<len;j++){ // row if(board[i][j]!=='.'){ if(row[parseInt(board[i][j])-0]){ return false; } row[parseInt(board[i][j])-0]=true; } // col if(board[j][i]!=='.'){ if(col[parseInt(board[j][i])-0]){ return false; } col[parseInt(board[j][i])-0]=true; } } } // cell for(var i=0;i<3;i++){ for(var j=0;j<3;j++){ var cell=[]; for(var k=0;k<10;k++){ cell[k]=false; } for(var r=3*i;r<3*i+3;r++){ for(var c=3*j;c<3*j+3;c++){ if(board[r][c]!=='.'){ if(cell[parseInt(board[r][c])-0]){ return false; } cell[parseInt(board[r][c])-0]=true; } } } } } return true; };