统计二叉树的叶结点个数。

#define _CRT_SECURE_NO_WARNINGS

#include <iostream>
using namespace std;

typedef char ElemType;
#define ERROR 0
#define OK 1
typedef struct BiNode
{
	ElemType data;
	BiNode* lchild, * rchild;
}BiNode,*BiTree;

bool Create_tree(BiTree& T)
{
	ElemType x = 0;
	scanf("%c", &x);
	if (x == '#')
	{
		T = NULL;
	}
	else
	{
		T = (BiTree)malloc(sizeof(BiNode));
		if (T == NULL)
		{
			cout << "内存无法分配!!!" << endl;
			return ERROR;
		}
		T->data = x;
		T->lchild = NULL;
		T->rchild = NULL;
		Create_tree(T->lchild);
		Create_tree(T->rchild);
	}
	return OK;
}

void PreOrder(BiTree T)
{
	if (T != NULL)
	{
		cout << T->data;
		PreOrder(T->lchild);
		PreOrder(T->rchild);
	}
}

void InOrder(BiTree T)
{
	if (T != NULL)
	{
		InOrder(T->lchild);
		cout << T->data;
		InOrder(T->rchild);
	}
}

void PostOrder(BiTree T)
{
	if (T != NULL)
	{
		PostOrder(T->lchild);
		PostOrder(T->rchild);
		cout << T->data;
	}
}

int leave_node_count(BiTree T)
{
	if (T == NULL)
	{
		return 0;
	}
	else if (T->lchild == NULL && T->rchild == NULL)
	{
		return 1;
	}
	else
	{
		return leave_node_count(T->lchild) + leave_node_count(T->rchild);
	}
}

//ABC##D##E##
//统计二叉树的叶结点个数
int main(void)
{
	BiTree T = NULL;
	Create_tree(T);
	PreOrder(T);
	cout << endl;
	InOrder(T);
	cout << endl;
	PostOrder(T);
	cout << endl;
	cout << "二叉树的叶结点个数：" << leave_node_count(T) << endl;
	return 0;
}