Created tree traversal in c

Author: avi181197

tree traversal using c

@@ -0,0 +1,118 @@
+//Binary tree traversal:
+ 
+#include <stdio.h>
+#include <conio.h>
+#include <malloc.h>
+struct node
+{
+    struct node *left;
+    int data;
+    struct node *right;
+};
+ 
+void main()
+{
+    void insert(struct node **,int);
+    void inorder(struct node *);
+    void postorder(struct node *);
+    void preorder(struct node *);
+ 
+    struct node *ptr;
+    int no,i,num;
+ 
+    ptr = NULL;
+    ptr->data=NULL;
+    clrscr();
+ 
+    printf("\nProgram for Tree Traversal\n");
+    printf("Enter the number of nodes to add to the tree.<BR>\n");
+    scanf("%d",&no);
+ 
+    for(i=0;i<no;i++)
+    {
+        printf("Enter the item\n");
+        scanf("%d",&num);
+        insert(&ptr,num);
+    }
+ 
+    //getch();
+    printf("\nINORDER TRAVERSAL\n");
+    inorder(ptr);
+ 
+    printf("\nPREORDER TRAVERSAL\n");
+    preorder(ptr);
+ 
+    printf("\nPOSTORDER TRAVERSAL\n");
+    postorder(ptr);
+ 
+    getch();
+}
+ 
+void insert(struct node **p,int num)
+{
+    if((*p)==NULL)
+    {
+        printf("Leaf node created.");
+        (*p)=malloc(sizeof(struct node));
+        (*p)->left = NULL;
+        (*p)->right = NULL;
+        (*p)->data = num;
+        return;
+    }
+    else
+    {
+        if(num==(*p)->data)
+        {
+            printf("\nREPEATED ENTRY ERROR VALUE REJECTED\n");
+            return;
+        }
+        if(num<(*p)->data)
+        {
+            printf("\nDirected to left link.\n");
+            insert(&((*p)->left),num);
+        }
+        else
+        {
+            printf("Directed to right link.\n");
+            insert(&((*p)->right),num);
+        }
+    }
+    return;
+}
+ 
+void inorder(struct node *p)
+{
+    if(p!=NULL)
+    {
+        inorder(p->left);
+        printf("\nData :%d",p->data);
+        inorder(p->right);
+    }
+    else
+    return;
+}
+ 
+void preorder(struct node *p)
+{
+    if(p!=NULL)
+    {
+        printf("\nData :%d",p->data);
+        preorder(p->left);
+        preorder(p->right);
+    }
+    else
+    return;
+}
+ 
+void postorder(struct node *p)
+{
+    if(p!=NULL)
+    {
+        postorder(p->left);
+        postorder(p->right);
+        printf("\nData :%d",p->data);
+    }
+    else
+    return;
+}
+