标签：style blog http color io strong ar for art
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.
思路：检查每一行、每一列以及9个3*3的子块是否满足要求即可。
1 class Solution { 2 public: 3 bool isValidSudoku( vector<vector<char> > &board ) { 4 short rowMark[9] = {0}, colMark[9] = {0}, squareMark[9] = {0}; 5 for( int i = 0; i < 9; ++i ) { 6 for( int j = 0; j < 9; ++j ) { 7 if( board[i][j] == ‘.‘ ) { continue; } 8 short bitflag = 1 << board[i][j]-‘1‘; 9 if( ( rowMark[i] | colMark[j] | squareMark[i/3*3+j/3] ) & bitflag ) { return false; } 10 rowMark[i] |= bitflag; 11 colMark[j] |= bitflag; 12 squareMark[i/3*3+j/3] |= bitflag; 13 } 14 } 15 return true; 16 } 17 };
标签：style blog http color io strong ar for art
原文地址：http://www.cnblogs.com/moderate-fish/p/3952427.html
