Stack Implementation in C




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

struct node {
    int value;
    struct node* next;
};

void display_stack( struct node** head);
int count( struct node **head);
void push( struct node** head, int val);
int pop( struct node** head);



int main(){

struct node *head;
head = NULL;
int item;

push(&head, 1);
push(&head, 2);
push(&head, 3);
push(&head, 4);
push(&head, 5);

display_stack( &head);

printf("The length of [STACK] is %d\n", count(&head));

printf("The element popped of [STACK] is %d\n", pop(&head));
printf("The element popped of [STACK] is %d\n", pop(&head));
printf("The element popped of [STACK] is %d\n", pop(&head));

printf("The length of [STACK] is %d\n", count(&head));

display_stack( &head);

return 0;
}


void display_stack( struct node** head){

    struct node* temp = *head;
    while( temp != NULL ){
        printf("The element in [STACK] is %d\n", temp->value);
        temp = temp->next;
    }
}


int count( struct node **head){
    struct node *temp;
    temp = *head;
    int count = 0;
    while( temp != NULL){
        count++;
        temp = temp->next;
    }
    return count;
}


void push( struct node** head, int val){

    struct node *temp;
    temp = (struct node*)malloc(sizeof(struct node));
    temp->value = val;
    temp->next = *head;
    *head = temp;
}


int pop( struct node** head){

    if( *head == NULL){
        printf( "The stack is empty");
        return 0;
    } else {
        struct node *temp = *head;
        *head = (*head)->next;
        return temp->value ;
    }
}