请你判断一个 9 x 9 的数独是否有效。只需要 根据以下规则 ,验证已经填入的数字是否有效即可。
数字 1-9 在每一行只能出现一次。
数字 1-9 在每一列只能出现一次。
数字 1-9 在每一个以粗实线分隔的 3x3 宫内只能出现一次。(请参考示例图)
注意:
一个有效的数独(部分已被填充)不一定是可解的。
只需要根据以上规则,验证已经填入的数字是否有效即可。
空白格用 '.' 表示。
示例 1:
输入:board =
[["5","3",".",".","7",".",".",".","."]
,["6",".",".","1","9","5",".",".","."]
,[".","9","8",".",".",".",".","6","."]
,["8",".",".",".","6",".",".",".","3"]
,["4",".",".","8",".","3",".",".","1"]
,["7",".",".",".","2",".",".",".","6"]
,[".","6",".",".",".",".","2","8","."]
,[".",".",".","4","1","9",".",".","5"]
,[".",".",".",".","8",".",".","7","9"]]
输出:true
示例 2:
输入:board =
[["8","3",".",".","7",".",".",".","."]
,["6",".",".","1","9","5",".",".","."]
,[".","9","8",".",".",".",".","6","."]
,["8",".",".",".","6",".",".",".","3"]
,["4",".",".","8",".","3",".",".","1"]
,["7",".",".",".","2",".",".",".","6"]
,[".","6",".",".",".",".","2","8","."]
,[".",".",".","4","1","9",".",".","5"]
,[".",".",".",".","8",".",".","7","9"]]
输出:false
解释:除了第一行的第一个数字从 5 改为 8 以外,空格内其他数字均与 示例1 相同。 但由于位于左上角的 3x3 宫内有两个 8 存在, 因此这个数独是无效的。
提示:
board.length == 9
board[i].length == 9
board[i][j] 是一位数字(1-9)或者 '.'
来源:力扣(LeetCode)
链接:https://leetcode-cn.com/problems/valid-sudoku
著作权归领扣网络所有。商业转载请联系官方授权,非商业转载请注明出处。
func isValidSudoku(board [][]byte) bool { boardLength := len(board) boardExcept := 3 for y := 0; y < boardLength; y++ { dx := map[byte]int{} dy := map[byte]int{} for x := 0; x < boardLength; x++ { valX := board[y][x] if valX != '.' { if _, ok := dx[valX]; ok { return false } else { dx[valX] = 1 } } valY := board[x][y] if valY != '.' { if _, ok := dy[valY]; ok { return false } else { dy[valY] = 1 } } } } for c1 := 0; c1 < boardExcept; c1++ { lz := [][]byte{} for y1 := 0; y1 < boardLength; y1++ { if y1/3 == c1 { lz = append(lz, board[y1]) } } for c2 := 0; c2 < boardExcept; c2++ { dz := map[byte]int{} for c3 := 0; c3 < boardExcept; c3++ { for c4 := 0; c4 < boardLength; c4++ { valZ := lz[c3][c4] if c4/3 == c2 { if valZ != '.' { if _, ok := dz[valZ]; ok { return false } else { dz[valZ] = 1 } } } } } } } return true }
class Solution: def isValidSudoku(self, board: List[List[str]]) -> bool: for y in range(9): lx = {} ly = {} for x in range(9): valX = board[y][x] if valX != ".": if lx.get(valX) == None: lx[valX] = 1 else: return False valY = board[x][y] if valY != ".": if ly.get(valY) == None: ly[valY] = 1 else: return False for j in range(3): lz1 = [] for i in range(9): if i // 3 == j: lz1.append(board[i]) for m in range(3): lz2 = [] for k in range(3): for n in range(9): if n // 3 == m and lz1[k][n] != ".": if lz1[k][n] in lz2: return False else: lz2.append(lz1[k][n]) return True
结束!