## 5 Temmuz 2008 Cumartesi

### Python sudoku solver

An easy solver. It doesn't make brute-force . So it's able to solve only simple sudokus where at least one field has no doubt about matcing only one number at any time.

```#!/usr/bin/python
# -*- coding: cp1254 -*-

#sample board
board=[[0,4,0,0,2,0,0,0,8],
[0,8,0,0,0,7,4,5,0],
[1,0,5,3,0,0,7,0,0],
[9,0,4,0,3,8,1,0,7],
[0,0,0,0,0,0,0,0,0],
[5,0,7,4,1,0,2,0,9],
[0,0,8,0,0,1,9,0,6],
[0,9,1,8,0,0,0,2,0],
[3,0,0,0,4,0,0,7,0]]

def get_row_suitables(y):
lst=range(1,10)
for x in range(0,9):
number=board[y][x]
if number:lst.remove(number)
return lst
def get_column_suitables(x):
lst=range(1,10)
for y in range(0,9):
number=board[y][x]
if number:lst.remove(number)
return lst
def get_square_suitables(y,x):
ystart=y-(y%3)
xstart=x-(x%3)
lst=range(1,10)
for y in range(ystart,ystart+3):
for x in range(xstart,xstart+3):
number=board[y][x]
if number:lst.remove(number)
return lst

def get_mutuals(a,b,c):
mutuals=[]
for i in a:
if b.count(i) and c.count(i): mutuals.append(i)
return mutuals
def total_zeros():
total=0
for y in range(0,9):
total+= board[y].count(0)
def print_board():
for y in range(0,9):print board[y]

#main loop
while True:
has_found_any=0
for y in range(0,9):
for x in range(0,9):
if not board[y][x]:
a=get_row_suitables(y)
b=get_column_suitables(x)
c=get_square_suitables(y,x)
d=get_mutuals(a,b,c)
if len(d)==1:
board[y][x]=d
has_found_any=1
elif len(d)==0:
print "Error! This sudoku is wrong."
break
else:
pass
if not total_zeros():
print "Sudoku solved succesfully"
print_board()
break
if not has_found_any:
print "Sudoku isn't solved"
break

```