first commit

include/Stack.h

@@ -0,0 +1,72 @@
+#ifndef STACK_H
+#define STACK_H
+#include <stdlib.h>
+
+struct stack_t
+{
+    struct stack_node_t *head;
+    struct stack_node_t *rear;
+
+    void (*enqueue)(struct stack_t *, int);
+    void (*dequeue)(struct stack_t *, int *);
+    void (*delete)(struct stack_t *);
+};
+
+struct stack_node_t
+{
+    int data;
+    struct stack_node_t *next;
+};
+
+void enqueue(struct stack_t *self, int v)
+{
+    struct stack_node_t *n = (struct stack_node_t *)malloc(sizeof(struct stack_node_t));
+    n->data = v;
+    n->next = NULL;
+
+    if (!self->head)
+    {
+        self->head = self->rear = n;
+        return;
+    }
+
+    self->rear->next = n;
+    self->rear = n;
+}
+
+void dequeue(struct stack_t *self, int *r)
+{
+    struct stack_node_t *p = self->head;
+    while (p)
+    {
+        if (p->next == self->rear)
+            break;
+        p = p->next;
+    }
+
+    *r = self->rear->data;
+    free(self->rear);
+    p->next = NULL;
+    self->rear = p;
+}
+
+void delete(struct stack_t *self)
+{
+    while (self->head)
+    {
+        struct stack_node_t *tmp = self->head;
+        self->head = self->head->next;
+        free(tmp);
+    }
+
+    self->head = NULL;
+    self->rear = NULL;
+}
+
+void init_stack(struct stack_t *s)
+{
+    s->head = NULL;
+    s->rear = NULL;
+}
+
+#endif // STACK_H