二叉树基本操作C代码

  1 #include<stdio.h>
  2 #include<malloc.h>
  3 #define LEN sizeof(struct ChainTree)
  4 struct ChainTree
  5 {
  6     int num;
  7     struct ChainTree *left;
  8     struct ChainTree *right;
  9 };
 10 /*函数功能：进行查找操作。*/
 11 ChainTree *BinTreeFind(ChainTree *bt,int data)//在二叉树中查找值为data的结点。
 12 {
 13     ChainTree *p;
 14     if(bt==NULL)
 15         return NULL;
 16     else
 17     {
 18         if(bt->num==data)
 19         return bt;
 20         else{
 21             if(p=BinTreeFind(bt->left,data))
 22                 return p;
 23              else if(p=BinTreeFind(bt->right,data))
 24                  return p;
 25              else
 26                  return NULL;
 27           }
 28     }
 29 }
 30 /*函数功能：先序遍历。*/
 31 void BinTree_DLR(ChainTree *bt)
 32 {
 33     if(bt)
 34     {
 35         printf("%d",bt->num);
 36         if(bt->left)
 37         {
 38             BinTree_DLR(bt->left);
 39         }
 40         if(bt->right)
 41         {
 42             BinTree_DLR(bt->right);
 43         }
 44     }
 45     return;
 46 }
 47 /*函数定义：后序遍历。*/
 48 void BinTree_LRD(ChainTree *bt)
 49 {
 50     if(bt)
 51     {
 52         BinTree_LRD(bt->left);
 53         BinTree_LRD(bt->right);
 54         printf("%d",bt->num);
 55     }
 56     return;
 57 }
 58 /*函数功能：中序遍历。*/
 59 void BinTree_LDR(ChainTree *bt)
 60 {
 61     if(bt)
 62     {
 63         BinTree_LDR(bt->left);
 64         printf("%d",bt->num);
 65         BinTree_LDR(bt->right);
 66     }
 67     return;
 68 }
 69 /*函数功能初始化一个二叉树，建立根节点。*/
 70 ChainTree *InitRoot()
 71 {
 72     ChainTree *node;
 73     node=(struct ChainTree*)malloc(LEN);
 74     printf("请输入根节点的值：");
 75     scanf("%d",&node->num);
 76     node->left=NULL;
 77     node->right=NULL;
 78     return node;
 79 }
 80
 81 /*添加数据到二叉树*/
 82 int BinTreeAddNode(ChainTree *bt,ChainTree *node,int n)
 83 {
 84     if(bt==NULL)
 85     {
 86         printf("\n父结点不在，请先设置父结点。");
 87         return 0;
 88     }
 89     switch(n)
 90     {
 91         case 1:
 92             if(bt->left)
 93             {
 94                 printf("左子树结点不为空。");
 95                 return 0;
 96             }
 97             else
 98                 bt->left=node;
 99             break;
100         case 2:
101             if(bt->right)
102             {
103                 printf("右子树结点不为空。");
104                 return 0;
105             }
106             else
107                 bt->right=node;
108             break;
109             default:
110                 printf("参数错误！\n");
111             return 0;
112     }
113     return 1;
114 }
115
116 /*函数功能：添加结点到二叉树。*/
117 void AddNode(ChainTree *bt)
118 {
119     int data;
120     int select;
121     ChainTree *node,*parent;
122     node=(struct ChainTree*)malloc(LEN);
123     printf("\n输入二叉树结点数据");
124     scanf("%d",&node->num);
125     node->left=NULL;
126     node->right=NULL;
127     printf("\n输入父结点数据：");
128     scanf("%d",&data);
129     parent=BinTreeFind(bt,data);
130     if(!parent)
131     {
132         printf("\n未找到父结点。");
133     }
134     printf("\n1.添加到左子树\n2.添加到右子树\n");
135     do{
136         scanf("%d",&select);
137         if(select==1||select==2)
138         BinTreeAddNode(parent,node,select);
139         }while(select!=1&&select!=2);
140 }
141
142 /*求二叉树叶子结点个数*/
143 void CountLeaf(ChainTree *bt,int &count)
144 {
145     if(bt)
146     {
147         if((!bt->left)&&(!bt->right))
148             count++;
149         CountLeaf(bt->left,count);
150         CountLeaf(bt->right,count);
151     }
152 }
153
154 /*求二叉树深度*/
155 int BinTreeDepth(ChainTree *bt)
156 {
157     int dep1,dep2;
158     if(bt==NULL)
159     return 0;
160     else
161     {
162         dep1=BinTreeDepth(bt->left);                //左子树深度（递归调用）
163         dep2=BinTreeDepth(bt->right);              //右子树深度（递归调用）
164         if(dep1>dep2)
165             return dep1+1;
166         else
167             return dep2+1;
168     }
169 }
170
171 int main()
172 {
173     struct ChainTree *p1,*p2,*head,*p3;
174     int select = 1000;
175     int countleaf=0;                                        //该变量计算叶子结点个数
176     while(select!=0){
177         printf("\n1.设置二叉树根元素\n2.添加二叉树根节点\n3.先序遍历\n4.中序遍历\n5.后序遍历\n6.输出叶子结点个数\n7.求二叉树深度\n0.退出");
178         scanf("%d",&select);
179         switch(select)
180         {
181         case 1:
182             head=InitRoot();
183             break;
184         case 2:
185             AddNode(head);
186             break;
187         case 3:
188             BinTree_DLR(head);
189             break;
190         case 4:
191              BinTree_LDR(head);
192              break;
193         case 5:
194             BinTree_LRD(head);
195             break;
196         case 6:
197                countleaf=0;                                              //求二叉树叶子结点数
198             CountLeaf(head,countleaf);
199             printf("\n%d",countleaf);
200             break;
201         case 7:
202             printf("二叉树深度为:%d\n",BinTreeDepth(head));
203              break;
204         case 0:
205             select = 0;
206             break;
207         }
208     }
209 }