fork download 
  1. #include <stdio.h>
  2. #include <stdlib.h>
  3.  
  4.  
  5.  
  6. typedef struct _stack
  7.     {
  8.  
  9.         struct _stack* prev;
  10.         struct _stack* next;
  11.         int value;
  12.  
  13.     } 
  14.     stack; 
  15.  
  16.  
  17. void push( int data );
  18. void pop(void);
  19.  
  20. stack *first = NULL;
  21. stack *real_first = NULL;
  22.  
  23. int main(void)
  24. {
  25.  
  26.  
  27.     push(22);
  28.     push(32);
  29.     push(42);
  30.     push(52);
  31.     push(4);
  32.     pop();
  33.     pop();
  34.     push(15);
  35.  
  36.  
  37.     stack *temp = real_first;
  38.  
  39.     while (temp  != NULL)
  40.     {   
  41.         printf("%i ", temp ->value);
  42.         temp  = temp->next;
  43.  
  44.     }
  45.  
  46.     temp = real_first;
  47.  
  48.      while (real_first != NULL)
  49.     {   
  50.         free(temp);
  51.         real_first = real_first->next;
  52.         temp  = real_first;
  53.  
  54.     }
  55.  
  56.  
  57.     printf("\n");
  58.     return 0;
  59. }
  60.  
  61.  
  62.  
  63.  
  64.  
  65. void push( int data)
  66. {
  67.     stack *newptr =  malloc(sizeof(stack));;
  68.     if (newptr == NULL)
  69.     {
  70.         return;
  71.     }
  72.  
  73.     newptr->value = data;
  74.  
  75.     newptr->prev = NULL;
  76.     if (first == NULL)
  77.     {
  78.         first = newptr;
  79.  
  80.         real_first = first;
  81.  
  82.     }
  83.  
  84.     else
  85.     {   
  86.  
  87.         newptr->prev = first;
  88.  
  89.         first->next = newptr;
  90.  
  91.         first = newptr;
  92.  
  93.     }
  94.  
  95.     return;  
  96. }
  97.  
  98.  
  99. void pop(void)
  100. {   
  101.     stack *tmp =  real_first;
  102.  
  103.     if ( real_first == NULL)
  104.         return;
  105.  
  106.     else if ( real_first->next == NULL)
  107.     {   free( real_first);
  108.          real_first = NULL;
  109.         return;
  110.     }
  111.     else
  112.     {
  113.  
  114.     while(real_first->next->next != NULL)
  115.     {
  116.     real_first= real_first->next;
  117.     }
  118.  
  119.     first = NULL;
  120.     first = real_first;
  121.     free(real_first->next);
  122.     real_first->next = NULL;
  123.  
  124.  
  125.     }
  126.      real_first =  tmp;
  127. }
Success #stdin #stdout 0s 2300KB
comments (?)
stdin 
Standard input is empty
stdout 
22 32 42 15
https://ideone.com/iTScte
language:
C (gcc 8.3)
created:
8 years ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!