二叉树遍历：已知前序和中序，求后序

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define MAX 1000

typedef struct node{
	char d;
	struct node *lchild,*rchild;
}Tnode;

void MK(char in[],int is,int ie,char pre[],int pres,int pree,Tnode **r){
	int i;
	if(is>ie||pres>pree){
		*r=NULL;
	}else{
		*r=(Tnode*)malloc(sizeof(Tnode));
		(*r)->d=pre[pres];//前序的第一个节点把中序分为左右子树
		for(i=is;i<=ie;i++){
			if(in[i]==pre[pres]){
				MK(in,is,i-1,pre,pres+1,pres+i-is,&(*r)->lchild);
				MK(in,i+1,ie,pre,pres+i-is+1,pree,&(*r)->rchild);
				break;
			}
		}
	}
}


void porder(Tnode *r){
	if(r){
		porder(r->lchild);
		porder(r->rchild);
		printf("%c",r->d);
	}
}


int leaf(Tnode *r){
	if(r==NULL){
		return 0;
	}else{
		if(!r->lchild&&!r->rchild){
			return 1;
		}else 
		return leaf(r->lchild)+leaf(r->rchild);
	}
}

int high(Tnode *r){
	int h1,h2;
	if(r==NULL){
		return 0;
	}else{
		h1=high(r->lchild);
		h2=high(r->rchild);
		return 1+(h1>h2?h1:h2);
	}
}

void main(){
	Tnode *r = NULL;
	char in[MAX],pre[MAX];
	printf("请输入前序序列：");
	gets(pre);
	printf("请输入中序序列：");
	gets(in);

	MK(in,0,strlen(in)-1,pre,0,strlen(pre)-1,&r);

	porder(r);

	printf("叶子节点的个数为：%d
",leaf(r));
	printf("二叉树的高度为：：%d
",high(r));
}