二叉树的定义与遍历

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

int meun() {

 int a = 0;
 printf("\n**************************************\n");
 printf("* 1.建立二叉链表树                   *\n");
 printf("* 2.显示先序，中序，后序列表         *\n");
 printf("* 3.统计叶节点，非叶结点，节点总数   *\n");
 printf("* 4.交换二叉树所有节点的左右子树     *\n");
 printf("* 5.帮助                             *\n");
 printf("* 6.退出                             *\n");
 printf("**************************************\n");
 printf("请输入菜单前的序号：");
 scanf_s("%d", &a);
 return a;

}

#define ElemType char
//节点声明，数据域、左孩子指针、右孩子指针
int SumNode = 0;
typedef struct BiTNode {
 char data;
 struct BiTNode *lchild, *rchild;
}BiTNode, *BiTree;
//先序建立二叉树
BiTree CreateBiTree() {
 char ch;
 BiTree T;
 ch = getchar();
 
 if (ch == '#') {
  T = NULL;
 }
 else {
  SumNode++;
  T = (BiTree)malloc(sizeof(BiTNode));
  T->data = ch;
  T->lchild = CreateBiTree();
  T->rchild = CreateBiTree();
 }
 return T;//返回根节点
}
//先序遍历二叉树
void PreOrderTraverse(BiTree T) {
 if (T) {
  printf("%c", T->data);
  PreOrderTraverse(T->lchild);
  PreOrderTraverse(T->rchild);
 }
}

//中序遍历
void InOrderTraverse(BiTree T) {
 if (T) {
  PreOrderTraverse(T->lchild);
  printf("%c", T->data);
  PreOrderTraverse(T->rchild);
 }
}
//后序遍历
void PostOrderTraverse(BiTree T) {
 if (T) {
  PreOrderTraverse(T->lchild);
  PreOrderTraverse(T->rchild);
  printf("%c", T->data);
 }
}

int GetSumNode() {  //节点总数
 return SumNode;
}

int SumLeaf(BiTree T)
{                         //求叶子节点的个数
 int sum = 0, m, n;
 if (T)
 {
  if ((!T->lchild) && (!T->rchild))
   sum++;
  m = SumLeaf(T->lchild);
  sum += m;
  n = SumLeaf(T->rchild);
  sum += n;
 }
 return sum;
}

int SumNoLeaf(BiTree T) //求非叶子节点的个数
{
 int sum = GetSumNode() - SumLeaf(T);                 
 
 return sum;
}

int Depth(BiTree T)   //求二叉树的深度
{
 int dep = 0, depl, depr;
 if (!T) dep = 0;
 else
 {
  depl = Depth(T->lchild);
  depr = Depth(T->rchild);
  dep = 1 + (depl > depr ? depl : depr);
 }
 printf("%d", dep);
 return dep;
}

void main() {

 BiTree T;
 T = CreateBiTree();
 bool loop = true;
 int a;
 while (loop) {
  a = meun();
  switch (a) {
  case 1:
   printf("请输入：\n");
   T = CreateBiTree();//建立
   break;
  case 2:
   printf("先序:\n");
   PreOrderTraverse(T);//输出
   printf("\n中序:\n");
   InOrderTraverse(T);
   printf("\n后序:\n");
   PostOrderTraverse(T);
   break;
  case 3:
   printf("节点总数:\n");
   printf("%d",GetSumNode());
   printf("\n叶节点数:\n");
   printf("%d",SumLeaf(T));
   printf("\n非叶节点数:\n");
   printf("%d", SumNoLeaf(T));
   
   break;
  case 4:
   break;
  case 5:
   break;
  case 6:
   break;
  }

 }
}