mobile wallpaper 1
mobile wallpaper 2
mobile wallpaper 3
mobile wallpaper 4
230 字
1 分钟
LeetCode 面试经典150题 [33/150 有效的数独]
2024-06-25

题目描述#

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

个人C++解答#

这边建议看官方题解,我写的就是shi,不过对于数独来说够用了,毕竟只有9个数; 官方题解:Leetcode【36.有效的数独】题解 https://leetcode.cn/problems/valid-sudoku/solutions/1001859/you-xiao-de-shu-du-by-leetcode-solution-50m6/

class Solution {
public:
bool isValidSudoku(vector<vector<char>>& board) {
int lin[10];
int col[10];
int reg[10];
for (int i = 0; i < 9; i++) {
for (int j = 0; j < 9; j++) {
if (board[i][j] != '.') {
if (lin[board[i][j] - '0'] != 0)
return false;
else
lin[board[i][j] - '0']++;
}
}
fill(lin, lin + 10, 0);
}
for (int i = 0; i < 9; i++) {
for (int j = 0; j < 9; j++) {
if (board[j][i] != '.') {
if (col[board[j][i] - '0'] != 0)
return false;
else
col[board[j][i] - '0']++;
}
}
fill(col, col + 10, 0);
}
for (int ii = 0; ii < 7; ii += 3) {
for (int jj = 0; jj < 7; jj += 3) {
for (int i = ii; i < ii + 3; i++) {
for (int j = jj; j < jj + 3; j++) {
if (board[i][j] != '.') {
if (reg[board[i][j] - '0'] != 0)
return false;
else
reg[board[i][j] - '0']++;
}
}
}
fill(reg, reg + 10, 0);
}
}
return true;
}
};
分享

如果这篇文章对你有帮助,欢迎分享给更多人!

LeetCode 面试经典150题 [33/150 有效的数独]
https://ericonline.cn/posts/leetcode-面试经典150题-33-150-有效的数独/
作者
Eric
发布于
2024-06-25
许可协议
CC BY-NC-SA 4.0

部分信息可能已经过时

目录