31_other_in_stack.c

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

//27-07-21

struct Node{
    int data;
    struct Node *next;
};

struct Node *top = NULL;

void linkedlistTraversal(struct Node *ptr){
    while (ptr != NULL)
    {
        printf("Element = %d\n", ptr->data);
        ptr = ptr->next;
    }
    
}

int isEmpty(struct Node *top){
    if (top == NULL)
    {
        // printf("!!Empty Linked list warning!!");
        return 1;
    }
    return 0;
}
int isFull(struct Node *top){
    struct Node *n = (struct Node *)malloc(sizeof(struct Node));
    if (n == NULL)
    {
        // printf("!!Heap memory Exhaustion warning!!");
        return 1;
    }
    
    return 0;
}



struct Node  *push(struct Node *top, int x){
    if (isFull(top))
    {
        printf("!!Heap memory Exhaustion warning!!\n");
    }
    struct Node *p = (struct Node *)malloc(sizeof(struct Node));
    p->data = x;
    p->next = top;
    top = p;
    return top;
}
//https://www.codewithharry.com/videos/data-structures-and-algorithms-in-hindi-30

int pop(struct Node **tp){
    if (isEmpty(*tp))
    {
        printf("!!Heap memory Exhaustion warning!!\n");
    }
    struct Node *p = *tp;
    *tp = (*tp)->next;
    int x = p->data;
    free(p);
    return x;
}

int peek(int position){
    struct Node *ptr = top;
    for (int i = 0; (i < position - 1 && ptr != NULL); i++)
    {
        ptr = ptr->next;
    }
    if (ptr != NULL)
    {
        return ptr->data;
        // printf("%d\n", ptr->data);
    }
    return -1;
}

int stackTop(){
    return top->data;
}
int stackBottom(){
    struct Node *ptr = top;
    while (ptr->next != NULL)
    {
        // printf("Element = %d\n", ptr->data);
        ptr = ptr->next;
    }
    return ptr->data;
}


int main(){
    top = push(top, 54);
    top = push(top, 55);
    top = push(top, 56);
    top = push(top, 57);
    linkedlistTraversal(top);
    top = push(top, 69);
    linkedlistTraversal(top);
    int element = pop(&top);
    printf("\n popedElement = %d\n", element);
    linkedlistTraversal(top);
    printf("------------------27-07\n");
    printf("%d\n",peek(2));
    // for (int i = 1; i <= 4; i++)
    // {
    //     printf("Value at position %d is : %d\n", i, peek(i));
    // }
    printf("%d\n", stackTop());
    printf("%d\n",stackBottom());
    
    
    return 0;
}