init commit

1 files changed, 45 insertions, 0 deletions

diff --git a/stack.c b/stack.c
new file mode 100644
index 0000000..c07c7fc
--- /dev/null
+++ b/stack.c
@@ -0,0 +1,45 @@
+#include <stdlib.h>
+
+typedef struct stack stack;
+
+typedef struct stack {
+	char *tape;	
+	int len;
+	char *ptr;
+} stack;
+
+stack *push(stack *s, char c){
+	if (s == NULL) {
+		stack *outstack = malloc(sizeof(stack));	
+		outstack->tape = malloc(1);
+		outstack->tape[0] = c;
+		outstack->ptr = outstack->tape;
+		outstack->len = 1;
+		return outstack;
+	}
+	s->len++;
+	s->ptr++;
+	s->tape = realloc(s->tape, s->len);
+	*s->ptr = c;
+
+	return s;
+}
+
+char pop(stack *s){
+	char c = *s->ptr;
+	*s->ptr = 0;
+	s->len--;
+	s->ptr--;
+	s->tape = realloc(s->tape, s->len);
+
+	return c;
+}
+
+char peek(stack *s){
+	return *s->ptr;
+}
+
+void cleanstack(stack *s){
+	free(s->tape);
+	free(s);
+}