# Very conscine solution 252ms in Java

• ``````public class Solution {
boolean[][] rows = new boolean[9][9];
boolean[][] cols = new boolean[9][9];
boolean[][] grids = new boolean[9][9];
boolean flag = false;
public void solveSudoku(char[][] board) {
if(board.length!=9) return;
if(board[0].length!=9) return;

for(int i=0;i<9;i++){//先记录一遍目前数独中的初始状态
for(int j=0;j<9;j++){
char c = board[i][j];
if(c=='.') continue;
rows[i][c-'1'] = true;
cols[j][c-'1'] = true;
grids[i/3*3+j/3][c-'1'] = true;
}
}
help(board,0,0);
}
public void help(char[][] board,int row,int col){
if(row>=9){//已经找到了数独的解
flag = true;
return;
}
char c = board[row][col];
if(c=='.'){//当前是一个空格
for(int i=0;i<=8;i++){//从1到9遍历的去尝试
if(rows[row][i]||cols[col][i]||grids[row/3*3+col/3][i]) continue;//新填入的数不能和数独中已有的状态产生冲突
rows[row][i] = true;
cols[col][i] = true;
grids[row/3*3+col/3][i] = true;
board[row][col] = (char)(i + '1');//暂时先填上这个数

if(col>=8) help(board,row+1,0);//到了该行的末尾，从下一行的头部开始
else help(board,row,col+1);//继续去考察下一格

if(flag) return;//如果已经找到答案了则直接返回
rows[row][i] = false;//尝试的当前数不合适，继续尝试下一个数
cols[col][i] = false;
grids[row/3*3+col/3][i] = false;
board[row][col] = '.';
}
}else if(col>=8) help(board,row+1,0);
else help(board,row,col+1);
}
``````

}

• 我觉得 这才是人写的代码。很好多谢

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