全部代碼

  1 #include <stdio.h>
  2 #include <stdlib.h>
  3 #include <assert.h>
  4 
  5 typedef struct node
  6 {
  7     int nValue;
  8     struct node *pLeft;
  9     struct node *pRight;
 10 }BiTree;
 11 
 12 typedef struct node2
 13 {
 14     BiTree *nValue;
 15     struct node2 *pNext;
 
 16 }MyStack;
 17 
 18 typedef struct node3
 19 {
 20     int nCount;
 21     MyStack *pTop;
 22 }Stack;
 23 
 24 void s_Init(Stack **ppStack)
 25 {
 26     assert(ppStack != NULL);
 27 
 28     *ppStack = (Stack *)malloc(sizeof(Stack));
 29     if(NULL == *ppStack)
 30     {
 31         printf("棧空間分配失敗！\n
 
");
 32         exit(-1);
 33     }
 34     (*ppStack)->nCount = 0;
 35     (*ppStack)->pTop = NULL;
 36 }
 37 
 38 void s_Push(Stack *pStack, BiTree *nNum)
 39 {
 40     MyStack *pTemp = NULL;
 41 
 42     assert(pStack != NULL);
 43 
 44     //臨時節點開辟空間
 45     pTemp = (MyStack *)malloc(sizeof(MyStack));
 
 46     if(NULL == pTemp)
 47     {
 48         printf("臨時節點空間分配失敗！\n");
 49         exit(-1);
 50     }
 51     pTemp->nValue = nNum;
 52     pTemp->pNext = NULL;
 53 
 54     //頭添加
 55     //臨時節點的下一個是頭節點
 56     pTemp->pNext = pStack->pTop;
 57     //新節點是新棧頂
 58     pStack->pTop = pTemp;
 59 
 60     //更新棧內元素
 61     ++pStack->nCount;
 62 }
 63 
 64 BiTree *s_Pop(Stack *pStack)
 65 {
 66     BiTree *nNum;
 67     MyStack *pDel = NULL;
 68 
 69     assert(pStack!=NULL && pStack->pTop!=NULL);
 70 
 71     //標記  要刪除的節點
 72     pDel = pStack->pTop;
 73     nNum = pStack->pTop->nValue;
 74     //棧頂指針下移
 75     pStack->pTop = pStack->pTop->pNext;
 76     //釋放空間
 77     free(pDel);
 78     pDel = NULL;
 79 
 80     //更新棧內元素
 81     --pStack->nCount;
 82 
 83     return nNum;
 84 }
 85 
 86 //遞歸創建二叉樹
 87 void RecCreateBiTree(BiTree **ppRoot)
 88 {
 89     int nNum;
 90 
 91     assert(ppRoot!=NULL);
 92 
 93     //輸入節點的值
 94     scanf("%d", &nNum);
 95 
 96     //檢測是否是結束標誌
 97     if(0 == nNum)
 98     {
 99         return;
100     }
101 
102     *ppRoot = (BiTree *)malloc(sizeof(BiTree));
103     if(NULL == *ppRoot)
104     {
105         printf("*ppRoot空間分配失敗！");
106         exit(-1);
107     }
108     (*ppRoot)->nValue = nNum;
109     (*ppRoot)->pLeft = NULL;
110     (*ppRoot)->pRight = NULL;
111 
112     //處理當前節點的左和右
113     RecCreateBiTree(&(*ppRoot)->pLeft);
114     RecCreateBiTree(&(*ppRoot)->pRight);
115 }
116 
117 //非遞歸前序遍歷
118 void UnRecPrevOrderTraversal(BiTree *pRoot)
119 {
120     Stack *pStack = NULL;
121 
122     assert(pRoot!=NULL);
123 
124     //申請輔助棧
125     s_Init(&pStack);
126 
127     while(1)
128     {
129         //打印根  處理左
130         while(pRoot!=NULL)
131         {
132             printf("%d ", pRoot->nValue);
133             s_Push(pStack, pRoot);
134             pRoot = pRoot->pLeft;
135         }
136 
137         //棧頂節點彈出  處理右子樹
138         pRoot = s_Pop(pStack);
139 
140         //棧空  樹遍歷結束
141         if(NULL == pRoot)
142         {
143             return;
144         }
145 
146         //處理右
147         pRoot = pRoot->pRight;
148     }
149 }
150 
151 //非遞歸中序遍歷
152 void UnRecMidOrderTraversal(BiTree *pRoot)
153 {
154     Stack *pStack = NULL;
155 
156     assert(pRoot!=NULL);
157 
158     //申請輔助棧
159     s_Init(&pStack);
160 
161     while(1)
162     {
163         //處理左
164         while(pRoot)
165         {
166             s_Push(pStack, pRoot);
167             pRoot = pRoot->pLeft;
168         }
169 
170         //棧頂節點彈出
171         pRoot = s_Pop(pStack);
172 
173         //棧空  樹遍歷結束
174         if(NULL == pRoot)
175         {
176             return;
177         }
178 
179         //打印左
180         printf("%d ", pRoot->nValue);
181 
182         //處理右
183         pRoot = pRoot->pRight;
184     }
185 }
186 
187 //非遞歸後序遍歷
188 void UnRecLastOrderTraversal(BiTree *pRoot)
189 {
190     Stack *pStack = NULL;
191     BiTree *pFlag = NULL;
192 
193     assert(pRoot!=NULL);
194 
195     //申請輔助棧
196     s_Init(&pStack);
197 
198     while(1)
199     {
200         //處理左
201         while(pRoot)
202         {
203             s_Push(pStack, pRoot);
204             pRoot = pRoot->pLeft;
205         }
206 
207         //空棧 結束
208         if(NULL == pStack->pTop)
209         {
210             return;
211         }
212 
213         //棧頂元素的右為空  或者已經被處理過 彈出  標記
214         if(NULL==pStack->pTop->nValue->pRight || pStack->pTop->nValue->pRight==pFlag)
215         {
216             pFlag = s_Pop(pStack);
217             printf("%d ", pFlag->nValue);
218         }
219         //未被處理過  繼續處理右
220         else
221         {
222             pRoot = pStack->pTop->nValue->pRight;
223         }
224     }
225 }
226 
227 int main(void)
228 {
229     BiTree *pRoot = NULL;
230     RecCreateBiTree(&pRoot);
231     UnRecPrevOrderTraversal(pRoot);
232     printf("\n");
233     UnRecMidOrderTraversal(pRoot);
234     printf("\n");
235     UnRecLastOrderTraversal(pRoot);
236     printf("\n");
237 
238     return 0;
239 }

二叉樹的非遞歸遍歷