General Tree
General tree is a tree in which each node can have either zero or many child nodes.
It can not be empty. In general tree, there is no limitation on the degree of a node.
The topmost node of a general tree is called the root node.
There are many subtrees in a general tree.
Example:
Electronics
|__Laptop
|__Mac
|__Surface
|__Thinkpad
|__Cell Phone
|__iPhone
|__Google Pixel
|__Vivo
|__TV
|__Samsung
|__LG