Saturday, 17 September 2016

Singly Linked List: Number of nodes in the list

Singly Linked List: Count number of nodes


#include<stdio.h>
#include<malloc.h>
#include<stdlib.h>

struct node
{
                int data;
                struct node *link;
};
typedef  struct node * NODE;


NODE getnode()
{
                NODE x;
                x = (NODE)malloc(sizeof(struct node));
                if(x==NULL)
                {
                                printf("\nInsufficient memory");
                                exit(0);
                }
                x->link = NULL;
                return x;
}

NODE insert(NODE first)
{
                int val;
                NODE temp, cur;
                temp = getnode();

                printf("\nEnter the value: ");
                scanf("%d", &val);
                temp->data = val;

                if(first==NULL)
                                return temp;

                cur = first;
                while(cur->link!=NULL)
                {
                                cur = cur->link;
                }
                cur->link = temp;
                return first;
}


void countnode(NODE first)
{
                NODE cur;
                int count=0;
                cur = first;
                while(cur!=NULL)
                {
                                count++;
                                cur = cur->link;
                }
                printf("\nTotal number of nodes are: %d", count);
}

void display(NODE first)
{
                 NODE cur;
                cur = first;
                printf("\nContents are:\n");
                if(cur == NULL)
                                printf("\nList is empty. Nothing to display.");
                else
                {
                                while(cur!=NULL)
                                {
                                                printf("| %d | %d | --> ", cur->data, cur->link);
                                                cur = cur->link;
                                }
                }
}


void main()
{
                int ch,i, n;
                NODE first = NULL;

                 printf("\nEnter number of nodes for list: ");
                scanf("%d",&n);
                for(i=0;i<n;i++)
                                first = insert(first);

                display(first);
                countnode(first);
}

Output:

Enter number of nodes for list: 5

Enter the value: 11
Enter the value: 12
Enter the value: 13
Enter the value: 14
Enter the value: 15

Contents are:
| 11 | 4986632 | --> | 12 | 4994056 | --> | 13 | 4994072 | --> | 14 | 4994088 | --> | 15 | 0 |