bool go(int i, int j, vector<vector<char>> &board) {
if (i > 8) return true;
if (board[i][j] != '.') {
next(i, j);
return go(i, j, board);
}
int i0 = i, j0 = j;
next(i, j);
for (int k=0; k<9; k++) {
if (check(i0, j0, k)) {
fill(i0, j0, k);
if (go(i, j, board)) {
board[i0][j0] = k+'1';
return true;
}
unfill(i0, j0, k);
}
}
return false;
}
inline void Puzzle::unplaceVolume(const Image* image)
{
unfill(image);
--pieceFill;
volumeMonitor.unplace(image->layout.size());
}
