README.md

Sudoku

generate a sample sudoku board player

def find_next_empty(puzzle):

# find the next row, col on the puzzle that's not filled yet --> rep wiith -1
# return row , col tuple ( or ( None , None ) if there is none)

# keep in mind that we are using 0-8 for our indices

def is_valid(puzzle , guess , row , col):

# figures out whether the suess at the row/col of the puzzle is a valif guess
# return True if is valid , False otherwise

# lets start with the row:

# now the column

# and then the square
# this is tricky , but we want to get where the 3x3 square starts
# and iterate over the 3 values in the row/column

# if we get here, these checks pass

def solve_sudoku(puzzle):

# solve sudoku using backtracking!
# our puzzle is a list of lists, where each inner list is a row in our sudoku puzzle
# return wether a solution exists
# mutates puzzle to be the solution ( if solution exists)

# step 1: choose somewhere on the puzzle to make a guess

# step 1.1 : if there's nowhere left, then we're done becasue we only allowed  valid inputs

# step 2 : if there is a place to put a number , then make a guess between 1 and 9
# step 3 : check if this is a valid guess
# step 3.1 : if this is valid, then place that guess on the puzzle!
# now recurse using this puzzle!
# step 4: recursively call our function
        
# step 5: if not valid OR if our guess doesn't solve puzzle, then we need to
# backtrack and try a new number
# reset the guess

# step 6: if none of the numbers that we try work, then this puzzle is unsolvable!

draw the board

<!-- example_board = [
    [3, 9, -1,  -1, 5, -1,  -1, -1, -1],
    [-1, -1, -1,    2, -1, -1,  -1, -1, 5],
    [-1, -1, -1,    7, 1, 9,    -1, 8, -1],

    [-1, 5, -1, -1, 6, 8,   -1, -1, -1],
    [2, -1, 6,  -1, -1, 3,  -1, -1, -1],
    [-1, -1, -1,    -1, -1, -1,    -1, -1, 4],

    [5, -1, -1, -1, -1, -1,    -1, -1, -1],
    [6, 7, -1,  1, -1, 5,   -1, 4, -1],
    [1, -1, 9,  -1, -1, -1,    2, -1, -1]
] -->