Answer key for SudokuValidator Challenge

SudokuValidator.js

/*  SudokuValidator(sudoku)
 *
 *  @param sudoku                       a multidimensional array containing the sudoku puzzle
 *
 *  @public property sudoku             the sudoku grid
 *
 *  @public method validate(num)        num is the squared value or max value of sudoku number
                                        for example: 9(result of 3x3 grid) or 4 (2x2).
 */

exports.SudokuValidator = SudokuValidator;

function SudokuValidator(sudoku){
  this.sudoku = sudoku;
}

SudokuValidator.prototype.validate = function(num){
  let sudoku = this.sudoku;

  let rows, cols, grid;

  organize(sudoku);

  function check (data){
    for (var row = 0; row < num; row++){
      data[row].sort();

      for(var col = 0; col < num; col++){
        let val = data[row][col]
        let nextVal = data[row][col + 1];
        if (!(val && val > 0 && val < num+1)){
          return false;
        }
        if (col !== num-1 && val === nextVal){
          return false;
        }
      }
    }
    return true;
  }

  function organize (data){
    rows = data;
    cols = [];
    grid = [];

    for (var i = 0; i < num; i++){
      cols.push([]);
      grid.push([]);
    }

    for (var row = 0; row < num; row++){
      for (var col = 0; col < num; col++){
        cols[col][row] = data[row][col];
        
        gridRow = Math.floor(row / Math.sqrt(num));
        gridCol = Math.floor(col / Math.sqrt(num));
        gridIndex = gridRow * Math.sqrt(num) + gridCol;

        grid[gridIndex].push(data[row][col]);
      }
    }
  }

  return (check(rows) && check(cols) && check(grid));
}