sudoku_solver.py

import random
class Solution:
	global recursion
	recursion = 0

	def is_full(self,arr):
		for i in arr:
			for j in i:
				if j == '.':
					return False
		return True

	def isValidSudoku(self,matrix,addedValue=None,location=None):
		if addedValue:
			arr[location[0]][location[1]] = addedValue

		for i in range(len(matrix)):
			row_arr = []
			for j in range(len(matrix)):
				if matrix[i][j] in row_arr:
					return False
				elif matrix[i][j] != ".":
					row_arr.append(matrix[i][j])

		for col in range(len(matrix)):
			col_arr = []
			# print("col_arr = "+str(col_arr))
			for i in range(len(matrix)):
				if matrix[i][col] in col_arr:
					return False
				elif matrix[i][col] != ".":
					col_arr.append(matrix[i][col])

		for g in (0,3,6):
			for h in (0,3,6):
				square_arr = []
				for i in range(g,g+3):
					for j in range(h,h+3):
						if matrix[i][j] in square_arr:
							return False
						elif matrix[i][j] != ".":
							square_arr.append( matrix[i][j])

		return True

	def solve_sudoku(self,arr):

		def get_possibles(arr):
			print(np.asarray(arr))
			table = {}
			for i in range(len(arr)):
				for j in range(len(arr)):
					if arr[i][j] != ".":
						if (i,j) in table:
							table.pop(i,j)
					else:
						table[i,j] = []
						for k in range(1,10):
							arr[i][j] = k
							if self.isValidSudoku(arr):
								table[i,j] = table[i,j]+[k]
						arr[i][j]="."
			return table

		def solve(arr):

			if self.is_full(arr):
				return arr
			i,list_ =  [(i,v) for i,v in sorted(get_possibles(arr).items(), key=lambda item:len(item[1])) ][0]
			i,j = i[0],i[1]
			for element in list_:
				print(i,j,element, "XXXXXXXXXXXXxx",list_)
				arr[i][j] = element
				solution = solve(arr)
				if solution:
					return solution
			
		return solve(arr)