sudoku.py

import numpy as np

grid = [[5,3,0,0,7,0,0,0,0],
        [6,0,0,1,9,5,0,0,0],
        [0,9,8,0,0,0,0,6,0],
        [8,0,0,0,6,0,0,0,3],
        [4,0,0,8,0,3,0,0,1],
        [7,0,0,0,2,0,0,0,6],
        [0,6,0,0,0,0,2,8,0],
        [0,0,0,4,1,9,0,0,5],
        [0,0,0,0,8,0,0,7,9]]

grid = np.matrix(grid)
print(grid)

def possible(y,x,n):
    for i in range(0,9):
        if grid[y,i]==n:
            return False
    for i in range(0,9):
        if grid[i,x]==n:
            return False
    x0=(x//3)*3
    y0=(y//3)*3
    for i in range(0,3):
        for j in range(0,3):
            if grid[y0+i,x0+j]==n:
                return False
    return True        

#print(possible(4,4,5))

def solve():
    #print(grid)
    for y in range(0,9):
        for x in range(0,9):
            if grid[y,x]==0:
                for n in range(1,10):
                    if(possible(y,x,n)):
                        grid[y,x]=n
                        solve()
                        grid[y,x]=0
                return
    print("after")
    print(grid)
    
    
solve()