Suodku solver - swift - being an interviewer 10:00 am - April 21, 2018

SudokuSolver.swift

//5 3 .
//6, . .
//.  9 8

// for eaech row
    
//  for column
//   if != "." {
// 

import Foundation

 func sudokuSolve(board: [[Character]]) -> Bool {
   var grid = board 
   for i in 0..<board.count {
     for j in 0..<board[0].count {
       if board[i][j] == "." {
          for n in 1..<10 {
            if isClear(Character(String(n)), i,j,&grid) {
              grid[i][j] = Character(String(n))
              if sudokuSolve(board: grid) {
                return true
              } else {
                grid[i][j] = "."
              }
            }
          }
         return false
       }
     }
   }
   return true
 }
 
 func isClear(_ num: Character,_ r: Int,_ c: Int,_ board: inout [[Character]]) -> Bool {
  
   for i in 0..<board.count {
     if board[r][i] != "." && board[r][i] == num {
       return false
     }
     if board[i][c] != "." && board[i][c] == num {
       return false
     }
     
     let row = 3 * (r / 3) + i / 3
     let column = 3 * (c / 3) + i % 3
     if board[row][column] != "." && board[row][column] == num {
       return false
     }
   }
    return true
  }