import java.util.Arrays;
public class ValidSudoku {
public boolean isValidSudoku(char[][] board) {
int row = board.length, col = board[0].length;
boolean[] f = new boolean[9];
for (int i = 0; i < row; i++) {
Arrays.fill(f, false);
for (int j = 0; j < col; j++) {
if (!check(board[i][j], f)) {
return false;
}
}
}
for (int i = 0; i < col; i++) {
Arrays.fill(f, false);
for (int j = 0; j < row; j++) {
if (!check(board[j][i], f)) {
return false;
}
}
}
for (int i = 0; i < 3; i++) {
for (int j = 0; j < 3; j++) {
Arrays.fill(f, false);
for (int m = 0; m < 3; m++) {
for (int n = 0; n < 3; n++) {
if (!check(board[i * 3 + m][j * 3 + n], f)) {
return false;
}
}
}
}
}
return true;
}
private boolean check(char c, boolean[] f) {
if (c == '.') {
return true;
} else if (f[c - '1']) {
return false;
} else {
f[c - '0'] = true;
return true;
}
}
}