树的建立递归非递归遍历

来源：互联网发布：青年网络公开课叶海林编辑：程序博客网时间：2024/05/16 03:05

//创建树
#include<iostream>
#include<malloc.h>
#define MAX 100
using namespace std;
typedef struct node
{
char data;
struct node *right,*left;
}btree;
void createTree(btree *&b,string s)
{
int top=-1;
btree *p,*stack[MAX];
int j=0;
int k;
b=NULL;
char c=s[j];
while(c!='/0')
    {
      switch(c)
    {
    case '(':top++;stack[top]=p;k=1;break;
    case ',':k=2;break;
    case ')':top--;break;
    default:
    p=(btree *)malloc(sizeof(btree));
    p->data=c;
    p->right=p->left=NULL;
    if(b==NULL)
        {
          b=p;
        }
    else
        {
          switch(k)
        {
        case 1:stack[top]->left=p;break;
        case 2:stack[top]->right=p;break;
        }
        }
    }
      j++;
      c=s[j];
    }
}
void printTree(btree *b)
{
if(b!=NULL)
    {
      cout<<b->data;
      if(b->left!=NULL || b->right!=NULL)
    {
    cout<<"(";
    printTree(b->left);
    if(b->right!=NULL)
        {
          cout<<",";
          printTree(b->right);

          cout<<")";
        }

    }
    }
}

void inorder_recursion(btree *b)
{
if(b!=NULL)
    {

      inorder_recursion(b->left);
      cout<<b->data<<" ";
      inorder_recursion(b->right);
    }
}
void firsOrder(btree *b)
{
btree *stack[MAX],*p;
int top=-1;
if(b!=NULL)
    {
      top++;
      stack[top]=b;
      while(top>=0)
   {
      p=stack[top];
      top--;
      cout<<p->data<<" ";
      if(p->right!=NULL)
        {
          top++;
          stack[top]=p->right;
        }
      if(p->left!=NULL)
        {
          top++;
          stack[top]=p->left;
        }
   }
    }
}

void firsOrderS(btree *b)
{
if(b!=NULL)
    {
      cout<<b->data<<" ";
      firsOrder(b->left);
      firsOrder(b->right);
    }
}
//我写的中序非递归遍历
void inorder(btree *b)
{
btree *p,*stack[MAX];
int top=-1;
int flag=0;
if(b!=NULL)
    {
      top++;
      stack[top]=b;
      while(top>=0)
   {
      p=stack[top];
      while(p->left!=NULL && !flag)
        {
          top++;
          p=p->left;
          stack[top]=p;

        }
      flag=1;
      p=stack[top];
      top--;
      cout<<p->data<<" ";
      if(p->right!=NULL)
        {
          top++;
          p=p->right;
          stack[top]=p;
          flag=0;
        }
   }
    }
}
void psorder_recursion(btree *b)
{
if(b!=NULL)
    {
      psorder_recursion(b->left);
      psorder_recursion(b->right);
      cout<<b->data<<" ";
    }
}

//这是我写的，不成功呀。
void psorder(btree *b)
{
btree *p,*stack[MAX];
int top=-1;
top++;
stack[top]=b;
int flag=0;
while(top>=0)
    {
      p=stack[top];
      while(p->left!=NULL && !flag)
   {
      top++;
      p=p->left;
      stack[top]=p;

   }
      if(flag==0)
   {
      p=stack[top];
      top--;
      cout<<p->data<<" ";
   }
      if(p->right!=NULL)
   {
      top++;
      p=p->right;
      stack[top]=p;
      flag=0;
   }
      else
   {
      p=stack[top];
      top--;
      cout<<p->data<<" ";
      flag=1;
   }

    }
}
/*
//写不出来了。
void psorder_b(btree *b)
{
btree *p,*stack[MAX];
int top=-1;
int flag;
if(b!=NULL)
    {
      top++;
     stack[top]=b;
     p=stack[top];
     do{
     while(b)
       {
   top++;
   stack[top]=b;
   b=b->left;
       }
     p=NULL;
     flag=1;
     while(top!=-1 && flag)
       {
   p=stack[top];
   top--;
   cout<<p->data<<" ";


       if(b->right==p)
         {
           top++;
           p=p->right;
           stack[top]=p;
           flag=1;
         }
       else
   {
       p=p->right;
       flag=0;
   }
       }
     }while(top!=-1);
    }
}
*/
void psorder_b(btree *b)
{
btree *p,*stack[MAX];
int top=-1;
int flag;
if(b!=NULL)
    {
     do{
while(b)
    {
      top++;
      stack[top]=b;
      b=b->left;
    }
p=NULL;
flag=1;
while(top!=-1 && flag)
      {
   b=stack[top];
      if(b->right==p)//p为空或已被访问过。
   {
      cout<<b->data<<" ";
      top--;
      p=b;
   }
      else
   {
      b=b->right;
      flag=0;
   }
      }
     }while(top!=-1);
    }

}
void psorder1(btree *b)
{
btree *p,*stack[MAX];
int top=-1;
int flag;
if(b!=NULL)
    {
      do
   {
      while(b)
   {
      top++;
      stack[top]=b;
      b=b->left;
   }
      p=NULL;
      flag=1;
      while(top!=-1 && flag)
   {
      b=stack[top];
      if(b->right==p)
        {
          cout<<b->data<<" ";
          top--;
          flag=1;
          p=b;
        }
      else
        {
          b=b->right;
          flag=0;
        }
   }
   }while(top!=-1);
    }

}
int main()
{
btree *b;
createTree(b,"a(b(c),d(e(,f),g))");
printTree(b);
cout<<endl;
inorder_recursion(b);
cout<<endl;
firsOrderS(b);
cout<<endl;
firsOrder(b);
cout<<endl;
inorder(b);
cout<<endl;
psorder_recursion(b);
cout<<endl;
// psorder(b);
cout<<endl;
psorder_b(b);
cout<<endl;
psorder1(b);
cout<<endl;
}

树的建立 递归非递归遍历

树的建立递归非递归遍历