Binary Tree
Binary tree is a special kind of tree where every parent can have at most two children.
These children are generally called left and right child of the parent node
All techniques that are useful in trees and graphs are also useful in binary trees
some pseudo code:
class node{
int val;
node *left, *right;
};
# pseudo code for recursive preOrder
preOrder(node *root){
if root is NULL
return;
else
visit(root)
preOrder(left);
preOrder(right);
}