Binary Tree Representation in C:
A tree is represented by a pointer to the topmost node in tree. If the tree is empty, then value of root is NULL.
A Tree node contains following parts.
2. Pointer to left child
3. Pointer to right child
In C, we can represent a tree node using structures. Below is an example of a tree node with an integer data.
First Simple Tree in C
Let us create a simple tree with 4 nodes in C. The created tree would be as following.
tree ---- 1 <-- root / \ 2 3 / 4
/* newNode() allocates a new node with the given data and NULL left and
right pointers. */
// Allocate memory for new node
node* node = (
// Assign data to this node
node->data = data;
// Initialize left and right children as NULL
node->left = NULL;
node->right = NULL;
node *root = newNode(1);
/* following is the tree after above statement
root->left = newNode(2);
root->right = newNode(3);
/* 2 and 3 become left and right children of 1
/ \ / \
NULL NULL NULL NULL
root->left->left = newNode(4);
/* 4 becomes left child of 2
/ \ / \
4 NULL NULL NULL