题解 | Sudoku
Sudoku
https://www.nowcoder.com/practice/78a1a4ebe8a34c93aac006c44f6bf8a1
l = [[int(i) for i in input().split()] for _ in range(9)]
lnumber = [1,2,3,4,5,6,7,8,9]
def yu():
global l
for i in range(9):
if len(set(l[i])) == 9:
if 0 in l[i]:
i0 = l[i].index(0)
if i0 >= 0:
for number in lnumber:
if number not in l[i]:
l[i][i0] = number
break
for j in range(9):
temp = [l[k][j] for k in range(9)]
if len(set(temp)) == 9:
if 0 in temp:
j0 = temp.index(0)
if j0 >= 0:
for number in lnumber:
if number not in temp:
l[j0][j] = number
break
for i in range(3):
for j in range(3):
temp = [l[3*i+k1][3*j+k2] for k1 in range(3) for k2 in range(3)]
if len(set(temp)) == 9:
if 0 in temp:
x0 = temp.index(0)
if x0 >=0:
for number in lnumber:
if number not in temp:
l[3*i+x0//3][3*j+x0%3] = number
break
def is_valid(x, y, num):
if num in l[x]:
return False
if num in [l[i][y] for i in range(9)]:
return False
for i in range(3):
for j in range(3):
if l[3 * (x // 3) + i][3 * (y // 3) + j] == num:
return False
return True
for _ in range(10):
yu()
def dfs():
global l
for x in range(9):
for y in range(9):
if l[x][y] == 0:
for number in lnumber:
if is_valid(x,y,number):
l[x][y] = number
if dfs():
return True
l[x][y] = 0
return False
return True
dfs()
for i in range(9):
print(" ".join(map(str,l[i])))
