Implementation of trees using linked list

1.Implementation of trees using linked list

#include
typedef struct node
{
    int data;
    struct node *left;
    struct node *right;
}node;
node *create()
{
    node *p;
    int x;
    printf(“Enter data(-1 for no
data):”);
    scanf(“%d”,&x);
    if(x==-1)
        return NULL;
    p=(node*)malloc(sizeof(node));
    p->data=x;
    printf(“Enter left child of
%d:n”,x);
    p->left=create();
    printf(“Enter right child of
%d:n”,x);
    p->right=create();
    return p;
}
void preorder(node *t)
              //address of root node is passed
in t
{
    if(t!=NULL)
    {    
printf(“n%d”,t->data);  
//visit the root
        preorder(t->left);          //preorder traversal on left subtree
        preorder(t->right);         //preorder traversal om right subtree
    }
}
int main()
{
    node *root;
    root=create();
    printf(“nThe preorder traversal of
tree is:n”);
    preorder(root);
    return 0;
}