static-data-structures/stack.c

   1 #include <stdio.h>
   2
   3 #define MAX_STACK_SIZE 16
   4
   5 struct data {
   6         int code;
   7 };
   8
   9 struct stack {
  10         struct data data[MAX_STACK_SIZE];
  11         int top;
  12 };
  13
  14 static void stack_init(struct stack *stack)
  15 {
  16         stack->top = 0;
  17 }
  18
  19 static int stack_emty(const struct stack *stack)
  20 {
  21         return stack->top == 0;
  22 }
  23
  24 static int stack_size(const struct stack *stack)
  25 {
  26         return stack->top;
  27 }
  28
  29 static int stack_push(struct stack *stack, struct data *data)
  30 {
  31         if (stack_size(stack) >= MAX_STACK_SIZE)
  32                 return -1;
  33
  34         stack->data[stack->top] = *data;
  35         stack->top++;
  36         return 0;
  37 }
  38
  39 static int stack_pop(struct stack *stack, struct data *data)
  40 {
  41         if (stack_emty(stack))
  42                 return -1;
  43
  44         stack->top--;
  45
  46         if (data)
  47                 *data = stack->data[stack->top];
  48         return 0;
  49 }
  50
  51 static void fill_data(struct data *data, int code)
  52 {
  53         data->code = code;
  54 }
  55
  56 int main(void)
  57 {
  58         struct stack stack;
  59         struct data data, data1, data2, data3, data4;
  60
  61         stack_init(&stack);
  62
  63         if (stack_emty(&stack))
  64                 printf("Stack is empty\n");
  65         else
  66                 printf("Stack is not empty\n");
  67
  68         fill_data(&data1, 1);
  69         fill_data(&data2, 2);
  70         fill_data(&data3, 3);
  71         fill_data(&data4, 4);
  72
  73         stack_push(&stack, &data1);
  74         stack_push(&stack, &data2);
  75         stack_push(&stack, &data3);
  76         stack_push(&stack, &data4);
  77
  78         if (stack_emty(&stack))
  79                 printf("Stack is empty\n");
  80         else
  81                 printf("Stack is not empty\n");
  82
  83         printf("Stack's size: %d\n", stack_size(&stack));
  84
  85         while (stack_pop(&stack, &data) == 0)
  86                 printf("%d\n", data.code);
  87
  88         if (stack_emty(&stack))
  89                 printf("Stack is empty\n");
  90         else
  91                 printf("Stack is not empty\n");
  92
  93         return 0;
  94 }