int countNodes(BiTree root) {
    if (root == NULL) return 0;
	else {
        return 1 + countNodes(root->lchild) + countNodes(root->rchild);
    }
}

void count_preorder(Bitree *t, int *n) { if(t!=NULL) {*n++; count_preorder(t->lchild); count_preorder(t->lchild); } }

int total_dfs(Tree& root) {
    if(root == NULL)  return 0;
    return total_dfs(root->left) + total_dfs(root->right) + 1;
}

int cnt = 0;
int total(BitTree *root)
{
	if(!root) return cnt;
	
	total(root -> l);
	total(root -> r);
	cnt ++;
	
	return cnt;
} 

int num;

int number(btree *r){

if(r){return 0 ;}

num++;

number(r->lifet);

number(r->right);

}

int NodeNum(BiTree *T){

    if(!T) return 0;

    else

        return 1 + NodeNum(T -> lchild) + NodeNum(T -> rchild);

}

typedef struct TreeNode{
    int val;
    struct TreeNode* left;
    struct TreeNode* right;
}TreeNode;

int count_node(TreeNode* root){
    if(!root) return 0;
    
    return 1 + count_node(root->left, root->right);
}

typedef struct TreeNode {     //定义二叉树结点
    int value;
    struct TreeNode* left;
    struct TreeNode* right;
} TreeNode;

int countNodes(TreeNode* root) {
    if (root == NULL)
        return 0;
    return 1 + countNodes(root->left) + countNodes(root->right);  //计算结点总数
}

int computedNode(Tree *t){

if(t==NULL) return 0;

int left=computedNode(t->lchild);

int right=computedNode(t->rchild);

return 1+left+right;

}

11

void count_preorder(Bitree *t, int *n)

    {

     if(t!=NULL)

{*n++;

count_preorder(t->lchild);

count_preorder(t->lchild); }

    }

return 1 + countNodes(t->lchild) + countNodes(t->rchild);

typedef struct BiNode{
	int data;
	struct BiNode *lchild,*rchild;
}BiNode,*BiTree;
int Sum(BiNode *T){
	if(T == NULL)
		return 0;
	else{
		return 1 + Sum(T->lchild) + Sum(T->rchild);
	}
}

/*求二叉树结点总数*/
int Count(Bintree T)
{
    if(T==NULL)
        return 0;                   /*空二叉树结点数为0*/
    else                            /*左右子树结点总数加1*/
        return Count(T->lchild)+Count(T->rchild)+1;
}

typedef struct BiTNode{

    int data;

    struct BiTNode *lchild,*rchild;

}BiTNode,*BiTree;

int count(BiTree T){

    if(T==NULL)

        return 0;

    else
        return 1+count(T->lchild)+count(T->rchild);

}

typedef struct BiNode{
	int data;
	struct BiNode *lchild,*rchild;
}BiNode,*BiTree;
int Sum(BiNode *T){
	if(T == NULL)
		return 0;
	else{
		return 1 + Sum(T->lchild) + Sum(T->rchild);
	}
}

int node_num(BiTree *t){
    if(t==NULL)  return 0;
    
    int cnt =1;
    cnt += node_num(t->lchild);
    cnt += node_num(t->rchild);
    
    return cnt ;
}

 void count(BiTree T){

      int n=0;

      if(T!=NULL){

            count(T->lchild);

            count(T->rchild);

            n++;

      }

      return n;

}

 void count(BiTree T){

      int n=0;

      if(T!=NULL){

            count(T->lchild);

            count(T->rchild);

            n++;

      }

      return n;

}

int GetNodesNum(BTNode * root)

{

if(root==NULL) return 0;

if(root->lchild)  return GetNodesNum(root->lchild)+1;

if(root->rchild) return GetNodesNum(root->rchild)+1;

return 1;

}

int func(BT root)

{if(root==NULL) return 0;

int sum=1;

return sum+func(BT->lchild)+func(BT->rchild);

}

#include <iostream>

// 二叉树节点结构
struct TreeNode {
    int data;
    TreeNode* left;
    TreeNode* right;
    TreeNode(int val) : data(val), left(nullptr), right(nullptr) {}
};

// 计算二叉树节点总数的递归函数
int countNodes(TreeNode* root) {
    if (root == nullptr) {
        return 0;  // 如果树为空，返回0
    }
    
    // 递归计算左子树和右子树的节点总数，然后加上根节点（1）
    int leftCount = countNodes(root->left);
    int rightCount = countNodes(root->right);
    return leftCount + rightCount + 1;
}

void count_preorder(Bitree *t, int *n){

  if(t!=NULL){

    *n++;

    count_preorder(t->lchild);

    count_preorder(t->lchild);

  }

}

int getSize(Tree* t){

if(t==NULL){

return 0;

}

int sum=0;

TreeNode* p=t;

if(p!=NULL){

sum=sum+getSize(p->lchild);

sum=sum+1;

sum=sum+getSize(p-rchild);

}

return sum;

}

void count_preorder(Bitree *t, int *n)

    {

     if(t!=NULL)

{*n++;

count_preorder(t->lchild);

count_preorder(t->lchild); }

    }

int nodenum(Bitree t){
    if(t)
        return 1+nodenum(t->lchild)+nodenum(t->rchild);
    else
        return 0;
}

int count(BTree *p)

{

    int sum=0;

    if(p!=NULL)

    {

        sum++;

        count(p->lchild);

        count(p->rchild);

    }

    return sum;

}

int sumpoint(BTNode *p)
{
    int n = 0;

    if (p != NULL)
    {
        n++;
        sumpoint(p->lchild);
        sumpoint(p->rchild);
    }

    return n;
}