diff --git a/builds/algo.o b/builds/algo.o
index 0999852..106a6d4 100644
Binary files a/builds/algo.o and b/builds/algo.o differ
diff --git a/builds/pushswap.o b/builds/pushswap.o
index 77f8165..e4811c0 100644
Binary files a/builds/pushswap.o and b/builds/pushswap.o differ
diff --git a/builds/stop.o b/builds/stop.o
index 812c4e8..45d914f 100644
Binary files a/builds/stop.o and b/builds/stop.o differ
diff --git a/pushswap b/pushswap
index 7b15bce..97457b7 100755
Binary files a/pushswap and b/pushswap differ
diff --git a/srcs/algo.c b/srcs/algo.c
index 8bd20a5..77a69c7 100644
--- a/srcs/algo.c
+++ b/srcs/algo.c
@@ -1,12 +1,78 @@
 
-
 #include "pushswap.h"
 
-t_list	*sort_algo(t_stack *stack)
+void	sa(t_list *pack)
 {
-	(void)stack;
-	t_list	*lst;
+	t_stack		*stack_a;
+	t_list		**solution;
+	int	tmp;
 
-	lst = ft_lstnew(ft_strdup("solution"));
-	return (lst);
+	stack_a = pack->content;
+	solution = pack->next->next->content;
+	if (!stack_a->next)
+		return ;
+	tmp = stack_a->n;
+	stack_a->n = stack_a->next->n;
+	stack_a->next->n = tmp;
+	(*solution)->content = ft_strdup("sa");
+	ft_lstadd_back(solution, ft_lstnew(NULL));
+}
+
+/*
+** this function 
+*/
+
+void	action(t_list *pack, void (*sp)(t_list *pack))
+{
+	t_stack		*stack_a;
+	t_stack		*stack_b;
+	t_list		**solution;
+
+	stack_a = pack->content;
+	stack_b = pack->next->content;
+	solution = pack->next->next->content;
+	print_stack(stack_a);
+	print_stack(stack_b);
+	ft_printf("%s\n", (*solution)->content);
+	sp(pack);
+}
+
+
+/*
+** this function create the structures "solution" and "stack_b"
+** and put their together with "stack_a" in "pack" to facilitate
+** the calls of functions. so pack contains :
+** - stack_a
+** - stack_b
+** - solution
+** then it calls the algorithm
+*/
+
+t_list	*sort_algo(t_stack *stack_a)
+{
+	t_stack		*stack_b;
+	t_list		*solution;
+	t_list		*pack;
+
+	solution = ft_lstnew(NULL);
+	if(!(stack_b = ft_calloc(1, sizeof(t_stack))))
+		ps_stop(stack_a, stack_b, solution, 2);
+	pack = ft_lstnew(stack_a);
+	ft_lstadd_back(&pack, ft_lstnew(stack_b));
+	ft_lstadd_back(&pack, ft_lstnew(&solution));
+	action(pack, sa);
+	print_stack(stack_a);
+	print_stack(stack_b);
+//	sa(stack_a, stack_b, &solution);
+//	sb(stack_a, stack_b, &solution);
+//	ss(stack_a, stack_b, &solution);
+//	pa(stack_a, stack_b, &solution);
+//	pb(stack_a, stack_b, &solution);
+//	ra(stack_a, stack_b, &solution);
+//	rb(stack_a, stack_b, &solution);
+//	rr(stack_a, stack_b, &solution);
+//	rra(stack_a, stack_b, &solution);
+//	rrb(stack_a, stack_b, &solution);
+//	rrr(stack_a, stack_b, &solution);
+	return (solution);
 }
diff --git a/srcs/pushswap.c b/srcs/pushswap.c
index 5ec7549..2c37871 100644
--- a/srcs/pushswap.c
+++ b/srcs/pushswap.c
@@ -33,9 +33,8 @@ int		main(int ac, char **av)
 
 	is_valid(ac, av); // check if usage and list are correct
 	stack = init_stack(ac, av); // create the list from av[]
-	print_stack(stack);
 	result = sort_algo(stack);
-	ft_printf("%s\n", result->content);
+	ft_printf("\n%s\n", result->content);
 	ps_stop(stack, NULL, result, 0);
 	return(0);
 }
diff --git a/srcs/stop.c b/srcs/stop.c
index 6f00162..570b95a 100644
--- a/srcs/stop.c
+++ b/srcs/stop.c
@@ -23,6 +23,9 @@ void	ps_stop(t_stack *stack_a, t_stack *stack_b, t_list *solution, int err)
 		ft_lstclear((t_list **)&stack_b, NULL);
 	if (solution)
 		ft_lstclear(&solution, free);
-	ps_error(err);
+	if (err < 0)
+		return ;
+	else if (err > 0)
+		ps_error(err);
 	exit(0);
 }