now version controlled.

1 files changed, 70 insertions, 0 deletions

diff --git a/que.c b/que.c
new file mode 100644
index 0000000..9ebee71
--- /dev/null
+++ b/que.c
@@ -0,0 +1,70 @@
+#include <u.h>
+#include <libc.h>
+
+typedef struct Node Node;
+struct Node {
+	int n;
+	Node *next;
+};
+
+Node *head, *tail;
+
+void *
+emalloc(ulong n)
+{
+	void *p;
+
+	p = malloc(n);
+	if(p == nil)
+		sysfatal("malloc: %r");
+	memset(p, 0, n);
+	setmalloctag(p, getcallerpc(&n));
+	return p;
+}
+
+void
+put(int n)
+{
+	if(tail == nil){
+		tail = emalloc(sizeof(Node));
+		tail->n = n;
+		head = tail;
+		return;
+	}
+	tail->next = emalloc(sizeof(Node));
+	tail = tail->next;
+	tail->n = n;
+}
+
+int
+get(void)
+{
+	Node *nn;
+	int n;
+
+	if(head == nil)
+		return -1;
+	nn = head->next;
+	n = head->n;
+	free(head);
+	head = nn;
+	return n;
+}
+
+int
+isemtpy(void)
+{
+	return head == nil;
+}
+
+void
+main()
+{
+	int i;
+
+	for(i = 0; i < 10; i++)
+		put(i*3);
+	while(!isemtpy())
+		print("%d\n", get());
+	exits(nil);
+}