tree *toBinaryTree(int pre[], int in[], int start, int end)
{
static int index = 0;
if(start > end)
{
return NULL;
}
tree *newnode = (tree *)malloc(sizeof(tree));
newnode->key = pre[index];
newnode->left = NULL;
newnode->right = NULL;
index++;
if(start == end)
{
return newnode;
}
int i, pos;
for(i = start; i <= end; i++)
{
if(in[i] == newnode->key)
{
pos = i;
}
}
newnode->left = toBinaryTree(pre, in, start, pos - 1);
newnode->right = toBinaryTree(pre, in, pos + 1, end);
return newnode;
}
cnode *toBinaryTree(cnode *head, cnode *tail)
{
cnode *root;
cnode *slow = head;
cnode *fast = head;
while (head != tail && fast != tail -> next && fast -> next != tail -> next)
{
slow = slow -> next;
fast = fast -> next -> next;
}
root = slow;
if (head -> info > tail -> info)
return NULL;
if (root -> previous != NULL)
root -> previous = toBinaryTree(head, root -> previous);
if (root -> next != NULL)
root -> next = toBinaryTree(root -> next, tail);
return(root);
}
int main()
{
int n, i;
scanf("%d", &n);
if(n <= 0)
{
printf("INVALID INPUT\n");
return 0;
}
int pre[n], in[n];
for(i = 0; i < n; i++)
{
scanf("%d", &pre[i]);
if(pre[i] >= 2147483648 || pre[i] <= -2147483648)
{
printf("INVALID INPUT\n");
return 0;
}
}
scanf("%d", &in[0]);
int max = in[0];
for(i = 1; i < n; i++)
{
scanf("%d", &in[i]);
if(in[i] < in[i - 1])
{
printf("INVALID INORDER TRAVERSAL\n");
return 0;
}
}
tree *root = toBinaryTree(pre, in, 0, n - 1);
preorder(root);
return 0;
}
int main()
{
printf("Enter numbers for doubly linked list in sorted order\n");
int holding = 0;
char junk = '.';
junk = getchar();
if (atoi(&junk) == 0 && junk != '0')
{
printf("Null list added, binary tree is null.\n");
exit(1);
}
int x = 1;
char *build = malloc(sizeof(char) * x);
char *tmp = '\0';
build[0] = '\0';
while (atoi(&junk) != 0 || junk == '0')
{
build[x-1] = junk;
junk = getchar();
x++;
tmp = realloc(build, sizeof(char) * x);
if (tmp != NULL)
build = tmp;
else
{
printf("Out of memory, program exit.");
free(build);
exit(3);
}
build[x-1] = '\0';
}
holding = atoi(build);
free(build);
cnode *head = malloc(sizeof(cnode));
head -> info = holding;
head -> previous = NULL;
head -> next = NULL;
cnode *tail = head;
while (junk == ' ')
{
scanf("%d", &holding);
if (holding < tail -> info)
{
printf("List is out of order, program exit.\n");
freeDoublyLinkedList(head, tail);
exit(2);
}
tail = insertTail(head, tail, holding);
junk = getchar();
}
printf("Doubly Linked List Contents:\n");
cnode *ptr = head;
while (ptr != NULL)
{
printf("%d ", ptr -> info);
ptr = ptr -> next;
}
printf("\n");
cnode *root = toBinaryTree(head, tail);
printf("Binary Search Tree Contents:\n");
printBinaryTree(root);
printf("\n");
freeBinaryTree(root);
return 0;
}
