include stdio include stdlib struct elem struct elem prev next int str

#include <stdio.h>
#include <stdlib.h>

struct elem
{
        struct elem *prev, *next;
	int v;
};

struct elem* initdoublelinkedlist()
{
	struct elem *list = (struct elem*)malloc(sizeof(struct elem));
	list -> prev = list;
	list -> next = list;
}

void insertafter(struct elem *x, struct elem *y)
{
	struct elem *z;
	z = x -> next;
	x -> next = y;
	y -> prev = x;
	y -> next = z;
	z -> prev = y;
}

void delete(struct elem *x)
{
	struct elem *y, *z;
	y = x -> prev,
        z = x -> next;
	y -> next = z;
	z -> prev = y;
	x -> prev = NULL;
	x -> next = NULL;
}

void insert_sort(struct elem *x)
{
	struct elem *y;
	struct elem *z;
	y = x -> next -> next;
	while(y != x) {
		z = y -> prev;
		while(z != x && y -> v < z -> v) {
			z = z -> prev;
		}
		delete(y);
		insertafter(z, y);
		y = y -> next;
	}
}

int main()
{
	struct elem *x = initdoublelinkedlist();
	struct elem	*y;
	int i, n;
	scanf("%d", &n);
	scanf("\n");

	for (i = 0; i < n; i ++) {
		y = initdoublelinkedlist();
		scanf("%d", &y -> v);
		insertafter(x, y);
	}

	insert_sort( x );
        y = x -> next;
	while (y != x) {
		printf("%d ", y -> v);
		printf("\n");
		y = y -> next;
	}

	y = x -> next;
	while (y != x) {
		free(y);
		y = y -> next;
	}

	free(x);
	return 0;
}