linked list example

[anthonye]

It's a while since I did linked lists is the following prog fine and if not why not.

#include<iostream.h>
#include<stdlib.h>
#include<conio.h>

#define MAX 30

	struct node{
    		  		int age;
                	char name[MAX];
                	node *next;  /* pointer to next node */
               };

int main()
{
    int amount;

	node *top;      /* pointers to a structure of type node */
    node *newnode;
    node *start;
    node *hold;

    top=(node*)malloc(sizeof(node)); /* set memory aside for first node */

    if(top==NULL)
        abort(); /* abnormal program termination */

    cout<<"How many people to be stored >";
    cin>>amount;

    if(amount==0)
    	{
    		free(top); /* only memory set aside for top node freed */
            exit(0);   /* terminate program */
        }

    cout<<"Input your name >";       /* we can only write to the top node(structure) at the moment */
    cin>>top->name;

    cout<<'\n'<<"Input your age";
    cin>>top->age;

    for(int start=1;start<amount;start++) /* start initialised to one as the first node has been filled */
    	{
        	newnode=(node*)malloc(sizeof(node));  /* set memory aside for the new node */

            top->next=newnode; /* pointer to top node points to next which is a pointer to a newnode */
                          /* which is assigned to next */

            cout<<'\n'<<"Input your name >";   /* write to next nodes */
            cin>>newnode->name;

            cout<<'\n'<<"Input your age";
            cin>>newnode->age;

            newnode->next=NULL; /* last node must point to NULL */
        }

    cout<<top->name<<' '<<top->age;
    cout<<'\n'<<newnode->name<<' '<<newnode->age;

    start=top; /* node pointer start points to top/first node in the list */

    for(int begin=0;begin<amount;begin++)
    	{
            hold=start; /* assign each node to a holding node so we can free */
                        /* its memory later */

            start=start->next; /* start is now pointing to the next node */

            if(hold!=NULL)
               	cout<<'\n'<<"Memory freed",free(hold);
        }

    getch();

    return 0;
}

Thanks for all the help.


Please use [code][/code]Tags

[sean]

Here is a good article on linked lists, with an example in C++.