public void InitHeaders(int ncolumns)
{
rootHeader = new ColumnHeader();
for (int i = 0; i<ncolumns; i++)
{
ColumnHeader header = new ColumnHeader();
columnHeaders.Add(header);
// embedding the header to the list among other headers
header.left = rootHeader.left;
header.right = rootHeader;
rootHeader.left.right = header;
rootHeader.left = header;
}
}
// uncover
void Restore(ColumnHeader colHeader)
{
//Iterate all the nodes in the column
for (Node row = colHeader.up; row != colHeader; row = row.up) {
//Reconnect vertically (add the row)
for (Node col = row.left; col != row; col = col.left)
{
col.header.count++;
col.down.up = col;
col.up.down = col;
}
}
//Reconnect the header
colHeader.right.left = colHeader;
colHeader.left.right = colHeader;
}
// cover
void Remove(ColumnHeader colHeader)
{
// Remove the header
colHeader.right.left = colHeader.left;
colHeader.left.right = colHeader.right;
// Iterate all the nodes in the column going down
for (Node row = colHeader.down; row != colHeader; row = row.down) {
// Remove the rows for every node
for (Node col = row.right; col != row; col = col.right) {
// Removing the items
col.down.up = col.up;
col.up.down = col.down;
col.header.count--;
}
}
}
