Merge pull request #29 from Naman-Bhalla/naman-pr

Include Data Structures and start with Binary Trees

data_structures/binary_trees/create_node.c

@@ -0,0 +1,39 @@
+/* Includes structure for a node and a newNode() function which
+   can be used to create a new node in the tree. 
+   It is assumed that the data in nodes will be an integer, though
+   function can be modified according to the data type, easily.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+struct node
+{
+    struct node *leftNode;
+    int data;
+    struct node *rightNode;
+};
+
+struct node *newNode(int data)
+{
+    struct node *node = (struct node *)malloc(sizeof(struct node));
+
+    node->leftNode = NULL;
+    node->data = data;
+    node->rightNode = NULL;
+
+    return node;
+}
+
+int main(void)
+{
+    /* new node can be created here as :-
+
+       struct node *nameOfNode = newNode(data);
+
+       and tree can be formed by creating further nodes at
+       nameOfNode->leftNode and so on.
+    */
+
+	return 0;
+}

data_structures/binary_trees/recursiveTraversals.c

@@ -0,0 +1,45 @@
+/* Includes the functions for Recursive Traversals
+   of a Binary Tree. It is assumed that nodes and
+   tree have been created as per create_node.c
+ */
+
+#include <stdio.h>
+
+void inOrderTraversal(struct node *node)
+{
+    if(node == NULL) //if tree is empty
+        return;
+
+    inOrderTraversal(node->leftNode);
+    printf("\t%d\t", node->data);
+    inOrderTraversal(node->rightNode);
+}
+
+void preOrderTraversal(struct node *node)
+{
+    if(node == NULL) //if tree is empty
+        return;
+
+    printf("\t%d\t", node->data);
+    preOrderTraversal(node->leftNode);
+    preOrderTraversal(node->rightNode);
+}
+
+void postOrderTraversal(struct node *node)
+{
+    if(node == NULL) //if tree is empty
+        return;
+
+    postOrderTraversal(node->leftNode);
+    postOrderTraversal(node->rightNode);
+    printf("\t%d\t",node->data);
+}
+
+int main(void)
+{
+    /* traversals can be done by simply invoking the
+       function with a pointer to the root node.
+    */
+
+	return 0;
+}