Sudoku solver - being an interviewer

SudokuSolver_BeInterviewer.cpp

#include <iostream>
#include <vector>

using namespace std;

bool fill(int k, int row, int col, bool cols[9][9], bool grids[3][3][9], bool rows[9][9]) {
  
  if(cols[col][k-1] == 1) 
    return false;
  
  if(rows[row][k-1] == 1) 
    return false;
  
  if(grids[row/3][col/3][k-1] == 1) 
    return false;
  
  cols[col][k-1] = 1;
  rows[row][k-1] = 1;
  grids[row/3][col/3][k-1] = 1;  
  
  return true; 
}

void unfill(int k, int row, int col, bool cols[9][9], bool grids[3][3][9], bool rows[9][9]) {
  cols[col][k-1] = 0;
  rows[row][k-1] = 0;
  grids[row/3][col/3][k-1] = 0;
}

bool recursion(int row, int col, bool cols[9][9], bool grids[3][3][9], bool rows[9][9], const vector<vector<char>>&board) {
  if(row >= 9 ){
    return true;
  }
  
  if(col >= 9) {
    return recursion(row + 1, 0, cols, grids, rows, board);
  }
  
  if(board[row][col] != '.') {
    return recursion(row, col + 1, cols, grids, rows, board);
  }
  
  for(int i = 1; i <= 9; i++) {
    if (fill(i, row, col, cols, grids, rows)) {
      if(recursion(row, col+1, cols, grids, rows, board)) 
        return true;      
      else unfill(i, row, col, cols, grids, rows);
    }
  }
  
  return false;
}

bool sudokuSolve(const vector<vector<char>>& board ) 
{
  bool rows[9][9] = {0}, cols[9][9] = {0}, grids[3][3][9] = {0};
  
  for(int i = 0; i < 9; i++) {
    for(int j = 0; j < 9; j++) {
      if(board[i][j] != '.') {
        if(!fill(board[i][j]-'0', i, j, cols, grids, rows)) return false;
      }
    }
  }
  
  return recursion(0, 0, cols, grids, rows, board);
  // your code goes here
}

/*

bool columns[9][9];
bool grids[9][9];
bool rows[9][9];



53..7.... 
6..195...
.98....6.
8...6...3
7...2...6
.6....28.
...419..5
....8..79


[".","8","9",".","4",".","6",".","5"]
[".","7",".",".",".","8",".","4","1"]
["5","6",".","9",".",".",".",".","8"]
[".",".",".","7",".","5",".","9","."]
[".","9",".","4",".","1",".","5","."]
[".","3",".","9",".","6",".","1","."]
["8",".",".",".",".",".",".",".","7"]
[".","2",".","8",".",".",".","6","."]
[".",".","6",".","7",".",".","8","."]]

*/

int main() {
  return 0;
}