C++ preorder函数代码示例

int main() {
    int n;
    scanf("%d", &n);
    int tree[n + 1][2], idx = 0;
    while (++idx <= n) {
        scanf("%d %d", &tree[idx][0], &tree[idx][1]);
    }
    preorder(tree, 1);
    printf("\n");
    inorder(tree, 1);
    printf("\n");
    postorder(tree, 1);
    return 0;
}

void bintree<T>::display()
{
 if(root==NULL)
	 cout<<"Tree Is Not Created";
 else
	 {
		cout<<"\n The Inorder Traversal of Tree is : ";
		inorder(root);
		cout<<"\n The Preoder Traversal of Tree is : ";
		preorder(root);
		cout<<"\n The Preoder Traversal of Tree is : ";
		postorder(root);
	 }
}

void main() {
  node root = NULL;

  root = insert(root, 10);
  root = insert(root, 20);
  root = insert(root, 30);
  root = insert(root, 40);
  root = insert(root, 50);
  root = insert(root, 25);

  printf("\nThe preorder traversal is: ");
  preorder(root);
  printf("\n");
}

int main(int argc, char *argv[]) {
  struct Node *root = new Node(1);
  root->left = new Node(2);
  root->right = new Node(3);
  root->left->left = new Node(4);
  root->left->right = new Node(5);
  root->right->left = new Node(6);
  root->right->right = new Node(7);

  std::cout << "Preorder Traversal(iterative): ";
  preorder(root);
  std::cout << "\n";
  return 0;
}

int main(void)
{
    Tree *root = (Tree *)malloc(sizeof(Tree));
    root->left = root->right = root->parent = NULL;
    root->val = INT_MIN;
    int i = 0;
    int minlen = INT_MAX;
    int templen = 0;

    for (i = 1; i <= 1024; i++) {
        insert(root, i);
    }
    preorder(root->left);
    printf("\n");

    for (i = 1; i <= 1024; i++) {
        find(root, i);
    }
    preorder(root->left);
    printf("\n");

    return 0;
}

void main()
{       int n,digit,g,o;
	node *insert(node *,int );
	void preorder(node *P);
	void inorder(node *P);
	void postorder(node *P);
	void deltree(void);
	do
	{
	printf("\tWhat do you want to do? \n");
	printf("\t\t 1) insert the element:\n");
	printf("\t\t 2) preorder traversal:\n");
	printf("\t\t 3) inorder traversal:\n");
	printf("\t\t 4) postorder traversal:\n");
	printf("\t\t 5) delete \n");
	scanf("%d",&n);
	switch(n)
	{
		case 1: printf("\tEnter the digit:\n");
			scanf("%d",&digit);
			while(digit!=0)
			{
				P=insert(P,digit);
				scanf("%d",&digit);
			}
			break;
		case 2: printf("\tThe preorder traversal is as follows:\n");
			preorder(P);
			getch();
			break;
		case 3: printf("\t The inorder traversal is as follows:\n");
			inorder(P);
			getch();
			break;
		case 4: printf("\t The postorder traversal is as follows:\n");
			postorder(P);
			getch();
			break;
		case 5: printf("\t delete\n");
			deltree();
			break;
	 }
		printf("\t DO you want to continue:\n");
		printf("\t 1)YES\n");
		printf("\t 2)NO\n");
		scanf("%d",&g);
		clrscr();

	 }while(g==1);
}

int main()
{
int pre[] = {5,3,6,2,7,1,4,8,9};
int in[] = {1,2,3,4,5,6,7,8,9};

struct BT *root = makeTree(in, pre, 0, sizeof(pre)/sizeof(pre[0]));

printf("\t====inordeer====\n");
inorder(root);
printf("\t====preordeer====\n");
preorder(root);

return 0;
}	

int main()
{
	struct node * root = newnode(1);
	root->left=newnode(2);
	root->right=newnode(3);
	root->left->left=newnode(4);
	root->left->right=newnode(5);
	printf("preorder\n");
	preorder(root);
	printf("INorder\n");
	inorder(root);
	printf("postorder\n");
	postorder(root);
	return 0;
}

 pair<TreeNode*, TreeNode*> preorder(TreeNode *root)
 {
     if(root == NULL)
         return make_pair(root, root);
     
     pair<TreeNode*, TreeNode*> left = preorder(root->left);
     pair<TreeNode*, TreeNode*> right = preorder(root->right);
     
     root->left = NULL;
     
     TreeNode *tail = root;
     
     if(left.first)
     {
         tail->right = left.first;
         tail = left.second;
     }
     if(right.first)
     {
         tail->right = right.first;
         tail = right.second;
     }
     return make_pair(root, tail);
 }

int main()
{
    int row = 3;//no. of input lines
    //1st element in each row is node Value, 2nd - no of child, ,>=3rd....=>value of child
    int data[3][5]={{1,3,2,3,4},{2,2,5,6,0},{3,3,8,9,10}};
    int i;
    struct tree* root=NULL;
    for(i=0;i<row;i++)
    {
 //       preorder(root);
        root = createnary(root,data[i]);
    }

    preorder(root);
}

int main(int argc, char *argv[]){

  element_type array[20];
  element_type array1[20];
  int i;  
  BTREE T1 = init_tree();
  BTREE T2 = init_tree();
  BTREE T3 = NULL;

  for(i=0; i<20; i++){
    array[i] = random(200);
    array1[i] = i;
    printf("%d ", array[i]);
  }
  printf("\n");

  T1 = creat_tree(array, sizeof(array)/sizeof(array[0]), T1);
  T2 = creat_tree(array, 1, T2);

  preorder(T1);
  printf("\n");
  preorder(T2);
  printf("\n");

  if(contain_tree(T1, T2))
    printf("T1 contains T2\n");
  else
    printf("T1 doesn't contain T2\n");

  free_tree(T1);
  free_tree(T2);

  return 0;

  
}

main()
{
	int choice,num;
	root=NULL;
	while(1)
	{
		printf("\n");
		printf("1.Insert\n");
		printf("2.Delete\n");
		printf("3.Inorder Traversal\n");
		printf("4.Preorder Traversal\n");
		printf("5.Postorder Traversal\n");
		printf("6.Display\n");
		printf("7.Quit\n");
		printf("Enter your choice : ");
		scanf("%d",&choice);

		switch(choice)
		{
		 case 1:
			printf("Enter the number to be inserted : ");
			scanf("%d",&num);
			insert(num);
			break;
		 case 2:
			printf("Enter the number to be deleted : ");
			scanf("%d",&num);
			del(num);
			break;
		 case 3:
			inorder(root);
			break;
		 case 4:
			preorder(root);
			break;
		 case 5:
			postorder(root);
			break;
		 case 6:
			display(root,1);
			break;
		 case 7:
			exit();
		 default:
			printf("Wrong choice\n");
		}/*End of switch */
	}/*End of while */
}/*End of main()*/

int main() 
{ 
	int n,x; 
	struct node *location,*parent; 
	do 
	{ 
		printf("1.insertion\n2.deletion\n3.search\n4.inorder traversal\n5.preorder traversal\n6.postorder\n7.exit\n"); 
		printf("\nenter ur choice\n"); 
		scanf("%d",&n); 
		switch(n) 
		{ 
			case 1: 
				printf("\nenter element to be inserted\n"); 
				scanf("%d",&x); 
				insert(x); 
				break; 
			case 2: 
				printf("\nenter element to be deleted\n"); 
				scanf("%d",&x); 
				del(x); 
				break; 
			case 3: 
				printf("\nenter element to be searched\n"); 
				scanf("%d",&x); 
				find(x,&parent,&location); 
				if(location!=NULL) 
				printf("\nsearch successfull\n"); 
				else 
				printf("\nitem not found\n"); 
				break; 
			case 4: 
				inorder(root); 
				break; 
			case 5: 
				preorder(root); 
				break; 
			case 6: 
				postorder(root); 
				break; 
			case 7: 
				return 0; 
				break; 
			default : 
				printf("\ndefault entry\n"); 
		} 
	} 
	while(n!=7); 
} 

int main(void)
{
	struct node* root = NULL;
	//struct node* root2 = NULL;
	struct node *find = NULL;

	char str[1024];

	root = insert(root, 10);
	root = insert(root, 15);
	root = insert(root, 9);
	root = insert(root, 8);
	root = insert(root, 13);
	root = insert(root, 7);
	root = insert(root, 5);
	root = insert(root, 18);
	root = insert(root, 22);
	root = insert(root, 3);
	root = insert(root, 4);
	root = insert(root, 2);
	root = insert(root, 1);
	print_ascii_tree(root);
	find = search(root, 18);
	print_ascii_tree(root);
	find = search(root, 22);
	printf("\n\n\nDATA found is %d\n", find->data);
	find = min_node(root);
	printf("Min in this tree is %d\n", find->data);
	find = max_node(root);
	printf("Mx in this tree is %d\n", find->data);
	print_ascii_tree(root);
	preorder(root);
	printf("\n");
	inorder(root);
	printf("\n");
	postorder(root);
	printf("\n");
	printf("DEPTH is %d\n", depth(root));
	tree_to_string(root, str);
	printf("The STR generated is %s\n", str);
	//string_to_tree(&root2, str);
	//print_ascii_tree(root2);
	printf("COUNT is %d\n",nodes(root));
	bool res = hassum(root, 45);
	printf("Bool val is %d\n", (int)res);
	levelorder(root);
	return 0;
}

int main()
{
	int n;
	scanf("%d",&n);
	int i;
	struct node* root=NULL;
	for(i=0;i<n;i++)
	{
		int a;
		scanf("%d",&a);
		insert(&root,a,NULL);
	}
	inorder(root);
	printf("\n");
	preorder(root);
	printf("\n");
	postorder(root);
	printf("\n");
	int search;
	scanf("%d",&search);
	int start=0;
	int end=k-1;
	while(start<=end)
	{
		if(arr[start]+arr[end]==search)
		{
			printf("%d %d",arr[start],arr[end]);
			break;
		}
		else if(arr[start]+arr[end]>search)
		{
			end--;
		}
		else
		{
			start++;
		}
	}
/*	searchi(root,search);
	//printf("%d",root->right->left->data);
	inorder(root);
	printf("\n");
	preorder(root);
	printf("\n");
	postorder(root);
	printf("\n");*/
	return 0;
}