Print Reverse a linked list using Stack



Given with a linked list program must print the list starting from the end till the front using the stack data structure

Input : 10 -> 5 -> 3 -> 1 -> 7 -> 9
Output: 9 -> 7 -> 1 -> 3 -> 5 -> 10

Here the user can use the approach of poping elements from the stack pointing top at the stack[0] location and than going till stack[n] element

Algorithm

START
Step 1 -> create structure Linked_list
   Declare int data
   Declare struct linked_list *next
End
Step 2 -> declare int stack[30], top = -1
Step 3 -> declare struct linked_list* head = NULL
Step 4 -> create function int printfromstack(int stack[])
   Loop While top>=0
   Print stack[--top]
End
Step 5 -> create function int push(struct linked_list** head, int n)
   declare struct linked_list* newnode = (struct linked_list*)malloc(sizeof(struct linked_list))
   set newnode->data = n
   set newnode->next = (*head)
   set (*head) = newnode
step 6 -> create function int intostack(struct linked_list* head)
   Loop While head!=NULL
      Print head->data
   Set stack[++top] = head->data
   Set head = head->next
   End
End
Step 7 -> goto main()
   Call push(&head, 10)
   Call push(&head, 20)
   Call push(&head, 30)
   Call push(&head, 40)
   Call intostack(head)
   Call printfromstack(stack)
STOP

Example

#include <stdio.h>
#include <stdlib.h>
struct linked_list {
   int data;
   struct linked_list *next;
};
int stack[30], top = -1;
struct linked_list* head = NULL;
int printfromstack(int stack[]) {
   printf("
Stack:
");    while(top>=0) {       printf("%d ", stack[top--]);    } } int push(struct linked_list** head, int n) {    struct linked_list* newnode = (struct linked_list*)malloc(sizeof(struct linked_list));    newnode->data = n;    newnode->next = (*head);    (*head) = newnode; } int intostack(struct linked_list* head) {    printf("Linked list:
");    while(head!=NULL) {       printf("%d ", head->data);       stack[++top] = head->data;       head = head->next;    } } int main(int argc, char const *argv[]) {    push(&head, 10);    push(&head, 20);    push(&head, 30);    push(&head, 40);    intostack(head);    printfromstack(stack);    return 0; }

Output

if we run the above program then it will generate the following output

Linked list:
40 30 20 10
Stack:
10 20 30 40

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