先序建树中序后序遍历及求叶子节点个数

#include<iostream> #include<cstdio> #include<stdlib.h> using namespace std; typedef struct node { char date; struct node *Tr,*Tl; }Ttree,*Titree; int s; void Creat(Titree *T) { char a; cin>>a; if(a=='-') *T=NULL; else { (*T)=(Titree)malloc(sizeof(Ttree)); (*T)->date=a; Creat(&(*T)->Tl); Creat(&(*T)->Tr); } } void zhongxu(Titree T) { if(T) { zhongxu(T->Tl); cout<<T->date<<" "; zhongxu(T->Tr); } } void houxu(Titree T) { if(T) { houxu(T->Tl); houxu(T->Tr); cout<<T->date<<" "; } } void qianxu(Titree T) { if(T) { cout<<T->date<<" "; if(!(T->Tl)&&!(T->Tr)) s++; qianxu(T->Tl); qianxu(T->Tr); } } int main() { Titree T; s=0; Creat(&T); zhongxu(T); cout<<endl; houxu(T); cout<<endl; qianxu(T); cout<<endl; cout<<s<<endl; system("pause"); }