数据结构之二叉树的各种运算

#include <iostream>
#include <malloc.h>
#define MaxSize 100
using namespace std;
typedef struct node
{
char data;
struct node *lchild;
struct node *rchild;
} BTNode;
void CreateBTNode(BTNode *&b,char *str)
{
BTNode *St[MaxSize],*p=NULL;
int top=-1,k,j=0;
char ch;
b=NULL;
ch=str[j];
while (ch!='\0')
{
switch(ch)
{
case '(':
top++;
St[top]=p;
k=1;
break;
case ')':
top--;
break;
case ',':
k=2;
break;
default:
p=(BTNode *)malloc(sizeof(BTNode));
p->data=ch;
p->lchild=p->rchild=NULL;
if (b==NULL)
b=p;
else
{
switch(k)
{
case 1:
St[top]->lchild=p;
break;
case 2:
St[top]->rchild=p;
break;
}
}
}
j++;
ch=str[j];
}
}
BTNode * FindNode(BTNode *b,char x)
{
BTNode *p;
if (b==NULL)
{
return NULL;
}
else if (b->data==x)
{
return b;
}
else
{
p=FindNode(b->lchild,x);
if (p!=NULL)
return p;
else
return FindNode(b->rchild,x);
}

}
BTNode *LchildNode(BTNode *p)
{
return p->lchild;
}
BTNode *RchildNode(BTNode *p)
{
return p->rchild;
}
int BTNodeHeight(BTNode *b)
{
int lchildh,rchildh;
if (b==NULL)
return 0;
else
{
lchildh=BTNodeHeight(b->lchild);
rchildh=BTNodeHeight(b->rchild);
return (lchildh>rchildh)?(lchildh+1):(rchildh+1);
}
}
void DispBTNode(BTNode *b)
{
if(b!=NULL)
{
cout<<b->data;
if (b->lchild!=NULL||b->rchild!=NULL)
{
cout<<"(";
DispBTNode(b->lchild);
if (b->rchild!=NULL)
cout<<",";
DispBTNode(b->rchild);
cout<<")";
}
}
}

int BTWidth(BTNode *b)  //求二叉树b的宽度
{
struct
{
int lno;		//节点的层次编号
BTNode *p;		//节点指针
} Qu[MaxSize];		//定义顺序非循环队列
int front,rear;							//定义队首和队尾指针
int lnum,max,i,n;
front=rear=0;							//置队列为空队
if (b!=NULL)
{
rear++;
Qu[rear].p=b;						//根节点指针入队
Qu[rear].lno=1;						//根节点的层次编号为1
while (rear!=front)					//队列不为空
{
front++;
b=Qu[front].p;					//队头出队
lnum=Qu[front].lno;
if (b->lchild!=NULL)			//左孩子入队
{
rear++;
Qu[rear].p=b->lchild;
Qu[rear].lno=lnum+1;
}
if (b->rchild!=NULL)			//右孩子入队
{
rear++;
Qu[rear].p=b->rchild;
Qu[rear].lno=lnum+1;
}
}
max=0;
lnum=1;
i=1;
while (i<=rear)
{
n=0;
while (i<=rear && Qu[i].lno==lnum)
{
n++;
i++;
}
lnum=Qu[i].lno;
if (n>max) max=n;
}
return max;
}
else
return 0;
}
int Nodes(BTNode *b)
{
int num1,num2;
if (b==NULL)
return 0;
else if (b->lchild==NULL && b->rchild==NULL)
return 1;
else
{
num1=Nodes(b->lchild);
num2=Nodes(b->rchild);
return (num1+num2+1);
}
}
int LeafNodes(BTNode *b)
{
int num1,num2;
if (b==NULL)
return 0;
else if (b->lchild==NULL && b->rchild==NULL)
return 1;
else
{
num1=LeafNodes(b->lchild);
num2=LeafNodes(b->rchild);
return (num1+num2);
}
}
void DestroyBTNode(BTNode *&b)
{
if (b!=NULL)
{
DestroyBTNode(b->lchild);
DestroyBTNode(b->rchild);
free(b);
}
}

int main()
{
BTNode *b,*p,*lp,*rp;
CreateBTNode(b,"A(B(D,E(H(J,K(L,M(,N))))),C(F,G(,I)))");
cout<<"(1)输出二叉树：";
DispBTNode(b);
cout<<endl;
cout<<"(2)输出H节点的左右孩子节点值:"<<endl;
p=FindNode(b,'H');
if (p!=NULL)
{
lp=LchildNode(p);
if (lp!=NULL)
cout<<"左孩子为："<<lp->data<<endl;
else
cout<<"无左孩子"<<endl;
rp=RchildNode(p);
if (rp!=NULL)
cout<<"右孩子为："<<rp->data<<endl;
else
cout<<"无左孩子"<<endl;
}
cout<<"(3)输出二叉树b的深度："<<BTNodeHeight(b)<<endl;
cout<<"(4)输出二叉树b的宽度："<<BTWidth(b)<<endl;
cout<<"(5)输出二叉树b的节点个数："<<Nodes(b)<<endl;
cout<<"(6)输出二叉树b的叶子节点个数："<<LeafNodes(b)<<endl;
cout<<"释放二叉树.";
DestroyBTNode(b);
return 0;
}