StackUsingLinkedList.c

#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#define CAPACITY 10000

struct stack {
  int data;
  struct stack *next;
} * top;

int size = 0;

void push(int element);
int pop();

int main() {
  int choice, data;

  while (1) {
    printf("------------------------------\n");
    printf(" STACK IMPLEMENTATION PROGRAM \n");
    printf("------------------------------\n");
    printf("1. Push\n");
    printf("2.Pop \n");
    printf("3.Size\n");
    printf("4.Exit\n");
    printf("\n");

    printf("Enter your choices:");
    scanf("%d", &choice);

    switch (choice) {
    case 1:
      printf("Enter data to push into stack: ");
      scanf("%d", &data);
      push(data);
      break;

    case 2:
      data = pop();

      if (data != INT_MIN)
        printf("Data=> %d\n", data);
      break;

    case 3:
      printf("Stack size: %d\n", size);
      break;

    case 4:
      printf("Exiting from the stack.\n");
      exit(0);
      break;

    default:
      printf("Invalid choice,please try again.\n");
    }
    printf("\n\n");
  }
  return 0;
}

void push(int element) {
  if (size >= CAPACITY) {
    printf("Stack overflow, can't add more element to stack.\n");
    return;
  }

  struct stack *newNode = (struct stack *)malloc(sizeof(struct stack));
  newNode->data = element;
  newNode->next = top;
  top = newNode;
  size++;
  printf("Data pushed into stack.\n");
}
int pop() {
  int data = 0;
  struct stack *topNode;

  if (size <= 0 || !top) {
    printf("Stack is empty.\n");
    return INT_MIN;
  }
  topNode = top;
  data = top->data;
  top = top->next;
  free(topNode);
  size--;
  return data;
}