tty-solitaire/lib/stack.c
2010-04-04 21:20:38 -03:00

60 lines
1.0 KiB
C

#include <malloc.h>
#include <stdbool.h>
#include "card.h"
#include "stack.h"
struct stack *initialize_stack() {
struct stack *stack = NULL;
stack = malloc(sizeof(*stack));
stack->card = NULL;
stack->next = NULL;
return(stack);
}
bool empty(struct stack *stack) {
return(stack->card == NULL);
}
int length(struct stack *stack) {
struct stack *iterator = stack;
int length = 0;
if (!empty(stack)) {
length = 1;
while (iterator->next != NULL) {
length++;
iterator = iterator->next;
}
}
return(length);
}
void push(struct stack **stack, struct card *card) {
struct stack *new_stack = NULL;
if (empty(*stack)) {
(*stack)->card = card;
} else {
new_stack = initialize_stack();
new_stack->card = card;
new_stack->next = (*stack);
*stack = new_stack;
}
}
struct stack *pop(struct stack **stack) {
struct stack *popped_entry = NULL;
if(!empty(*stack)) {
popped_entry = *stack;
*stack = (*stack)->next;
popped_entry->next = NULL;
}
return(popped_entry);
}