统计二叉树中叶子结点个数

#include
#include

typedef char ElemType;
typedef struct BTNode
{
	ElemType data;
	struct BTNode *left;
	struct BTNode *right;
}BTNode,*BiTree;

//创建二叉树
void createBTNode(BiTree &BT)
{
	ElemType ch;
	scanf("%c",&ch);
	if(ch==' ')
		BT=NULL;
	else
	{
		BT = (BTNode*)malloc(sizeof(BTNode));
		BT->data= ch;
		createBTNode(BT->left);
		createBTNode(BT->right);
	}
}

//先序遍历二叉树
void printDLR(BiTree BT)
{
	if(BT)
	{
		printf("%c ",BT->data);
		printDLR(BT->left);
		printDLR(BT->right);
	}
}

//统计二叉树结点个数
void countLeaves(BiTree BT,int &count)
{
	if(BT)
	{
		if(BT->left==NULL && BT->right==NULL)
		count++;
		else{
			countLeaves(BT->left,count);
			countLeaves(BT->right,count);
		}
	}
}

void main()
{
	BTNode *BT;
	int count=0;
	createBTNode(BT);
	printf("先序遍历：");
	printDLR(BT);
	printf("n");
	countLeaves(BT,count);
	printf("二叉树结点的个数：%dn",count);
}

按照先序遍历的方式来输入二叉树结点，若孩子结点为空，则输入空格。

输入：

ABD  E  CF

返回结果：

先序遍历：A B D E C F

二叉树结点的个数：3

叶子结点分别是：D、E、F