36. Valid Sudoku(合法数独)

Determine if a Sudoku is valid, according to:Sudoku Puzzles - The Rules.

The Sudoku board could be partially filled, where empty cells are filled with the character'.'.


A partially filled sudoku which is valid.


Note:
A valid Sudoku board (partially filled) is not necessarily solvable. Only the filled cells need to be validated.

关于数独的简介：

There are just 3 rules to Sudoku.

1.Each row must have the numbers 1-9 occuring just once.

2.Each column must have the numbers 1-9 occuring just once.

3.And the numbers 1-9 must occur just once in each of the 9 sub-boxes of the grid.

题目大意：

判断一个给定的二维数组是否是一个合法的数独矩阵。

思路:

采用set这一容器，来进行去重。

1.判断每一行是否合法。

2.判断每一列是否合法。

3.判断每一个九宫格是否合法。

代码如下：

classSolution{public:boolisValidSudoku(vector<vector<char>>&board){set<char>mySet;//1.判断每一行是否合法for(introw=0;row<9;row++){//cout<<"检测行:"<<row<<endl;for(intcolumn=0;column<9;column++){if(board[row][column]=='.'){continue;}if(mySet.find(board[row][column])==mySet.end()){mySet.insert(board[row][column]);}else{returnfalse;}}mySet.clear();}//2.判断每一列是否合法for(introw=0;row<9;row++){//cout<<"检测列:"<<row<<endl;for(intcolumn=0;column<9;column++){if(board[column][row]=='.'){continue;}if(mySet.find(board[column][row])==mySet.end()){mySet.insert(board[column][row]);}else{returnfalse;}}mySet.clear();}//3.判断每一个九宫格是否合法for(introw=0;row<9;row+=3){for(intcolumn=0;column<9;column+=3){for(inti=row;i<row+3;i++){for(intj=column;j<column+3;j++){if(board[i][j]=='.'){continue;}if(mySet.find(board[i][j])==mySet.end()){mySet.insert(board[i][j]);}else{returnfalse;}}}mySet.clear();}}returntrue;}};

2016-08-13 12:21:54