Code:
#include stdio.h
#include stdlib.h
struct node
{
int num;
struct node *next;
};
void create(struct node **);
void middlenode(struct node *);
void release(struct node **);
int main()
{
struct node *p = NULL;
printf("Enter data into the list\n");
create(&p);
middlenode(p);
release (&p);
return 0;
}
void middlenode(struct node *head)
{
struct node *p, *q;
int flag = 0;
q = p = head;
/*for every two hops of q, one hop for p*/
while (q->next != NULL)
{
q = q->next;
if (flag)
{
p = p->next;
}
flag = !flag;
}
if (flag)
{
printf("List contains even number of nodes\nThe middle two node's values are: %d %d\n", p->next->num, p->num);
}
else
{
printf("The middle node of the list is: %d\n", p->num);
}
}
void create(struct node **head)
{
int c, ch;
struct node *temp;
do
{
printf("Enter number: ");
scanf("%d", &c);
temp = (struct node *)malloc(sizeof(struct node));
temp->num = c;
temp->next = *head;
*head = temp;
printf("Do you wish to continue [1/0]: ");
scanf("%d", &ch);
} while (ch != 0);
printf("\n");
}
void release(struct node **head)
{
struct node *temp = *head;
*head = (*head)->next;
while ((*head) != NULL)
{
free(temp);
temp = *head;
(*head) = (*head)->next;
}
}
Output:
Enter data into the list
Enter number: 1
Do you wish to continue [1/0]: 1
Enter number: 2
Do you wish to continue [1/0]: 1
Enter number: 3
Do you wish to continue [1/0]: 1
Enter number: 4
Do you wish to continue [1/0]: 1
Enter number: 5
Do you wish to continue [1/0]: 0
The middle node of the list is: 3
More C Programs:
