Files
42_INT_06_pushwap/srcs/algo.c
2021-09-27 00:28:46 +02:00

152 lines
2.8 KiB
C

#include "push_swap.h"
// size is initialized to 1 because the loop check the next element, so it will end one step before reaching it
// it checks the next one to avoid handle the first one with ->limit set to 1
int sublist_size(t_stack *list)
{
int size;
if (list == NULL)
return (0);
size = 1;
while (list->next != NULL && list->next->limit != 1)
{
list = list->next;
size++;
}
return (size);
}
int nbr_element_smaller(t_stack *list, int size, int pivot)
{
int nbr;
nbr = 0;
while (size-- > 0)
{
if (list->n < pivot)
nbr++;
list = list->next;
}
return (nbr);
}
// pivot is the smallest of the bigger group
int find_pivot(t_stack *list, int size)
{
int pivot;
t_stack *head;
pivot = list->n;
head = list;
while (head->next && nbr_element_smaller(list, size, pivot) != size / 2)
{
head = head->next;
pivot = head->n;
}
return (pivot);
}
int divide_a(t_stack **a, t_stack **b, t_list *solution)
{
int list_size;
int pivot;
t_stack *first_rotate;
first_rotate = NULL;
list_size = sublist_size(*a);
pivot = find_pivot(*a, list_size);
(*a)->limit = 0;
while (list_size-- > 0)
{
if ((*a)->n >= pivot)
{
if (!first_rotate)
first_rotate = *a;
ra(a, &solution);
}
else
pb(b, a, &solution);
}
while (*a != first_rotate)
rra(a, &solution);
(*a)->limit = 1;
(*b)->limit = 1;
mark_step(solution, "divide_a");
return (0);
}
int divide_b(t_stack **a, t_stack **b, t_list *solution)
{
int list_size;
int pivot;
t_stack *first_rotate;
first_rotate = NULL;
list_size = sublist_size(*b);
pivot = find_pivot(*b, list_size);
(*b)->limit = 0;
while (list_size-- > 0)
{
if ((*b)->n >= pivot)
pa(a, b, &solution);
else
{
if (!first_rotate)
first_rotate = *b;
rb(b, &solution);
}
}
while (*b != first_rotate)
rrb(b, &solution);
(*a)->limit = 1;
(*b)->limit = 1;
mark_step(solution, "divide_b");
return (0);
}
void send_sublist_to_a(t_stack **a, t_stack **b, t_list *solution)
{
int list_size;
list_size = sublist_size(*b);
(*b)->limit = 0;
while (list_size-- > 0)
pa(a, b, &solution);
(*a)->limit = 1;
if (*b)
(*b)->limit = 1;
mark_step(solution, "send_sublist_to_a");
}
void recursif_sort(t_stack **a, t_stack **b, t_list *solution)
{
if (sublist_size(*a) > 4)
divide_a(a, b, solution);
else
{
// sort_big(a, b, solution)
mini_sort(a, solution);
// minisort(a, solution);
if (sublist_size(*b) > 4)
divide_b(a, b, solution);
else if (sublist_size(*b) > 0)
send_sublist_to_a(a, b, solution);
else
return ;
}
recursif_sort(a, b, solution);
}
void hugo_sort(t_stack **a, t_stack **b, t_list *solution)
{
if (sublist_size(*a) <= 3)
special_sort_3(a, b, solution);
else if (sublist_size(*a) <= 5)
special_sort_5(a, b, solution);
else
recursif_sort(a, b, solution);
}