1 #ifndef _Tree_H
2
3 struct TreeNode;
4 typedef struct TreeNode *Position;
5 typedef struct TreeNode *SearchTree;
6
7 SearchTree MakeEmpty(SearchTree T);
8 Position Find(ElementType X, SearchTree T);
9 Position FindMin(SearchTree T);
10 Position FindMax(SearchTree T);
11 SearchTree Insert(ElementType X, SearchTree T);
12 SearcgTree Delete(ElementType X, SearchTree T);
13 ElementType Retrieve(Position P);
14
15 #endif
16
17 struct TreeNode
18 {
19 ElementType Element;
20 SearchTree Left;
21 SearchTree Right;
22 };
23
24
25 SearchTree MakeEmpty(SearchTree T)
26 {
27 if (T != NULL)
28 {
29 MakeEmpty(T->Left);
30 MakeEmpty(T->Right);
31 free(T);
32 }
33 return NULL;
34 }
35
36
37 Position Find(ElementType X, SearchTree T)
38 {
39 if (T == NULL)
40 return NULL;
41 if (X < T->Element)
42 return Find(X, T->Left);
43 else if (X > T->Element)
44 return Find(X, T->Right);
45 else
46 return T;
47 }
48
49
50 Position FindMin(SearchTree T)
51 {
52 if (T == NULL)
53 return NULL;
54 else if (T->Left == NULL)
55 return T;
56 else
57 return FindMin(T->Left);
58 }
59
60 Position FindMax(SearchTree T)
61 {
62 if (T != NULL)
63 while (T->Right != NULL)
64 T = T->Right;
65 return T;
66 }
67
68
69 SearchTree Insert(ElementType X, SearchTree T)
70 {
71 if (T == NULL)
72 {
73 T = malloc(sizeof(struct TreeNode));
74 if (T = NULL)
75 perror("Out of Space");
76 else
77 {
78 T->Element = X;
79 T->Left = T->Right = NULL;
80 }
81 }
82 else if (X < T->Element)
83 T->Left = Insert(X, T->Left);
84 else
85 T->Right = Insert(X, T->Right);
86
87 return T;
88 }
89
90
91 SearchTree Delete(ElementType X, SearchTree T)
92 {
93 Position TmpCell;
94
95 if (T == NULL)
96 perror("Element not found");
97 else if (X < T->Left)
98 T->Left = Delete(X, T->Left);
99 else if(X > T-Right)
100 T->Right = Delete(X, T->Right);
101
102 else if (T->Left && T->Right)
103 {
104 TmpCell = FindMin(T->Right);
105 T->Element = TmpCell->Element;
106 T->Right = Delete(T->Element, T->Right);
107 }
108 else
109 {
110 TmpCell = T;
111 if (T->Left == NULL)
112 T = T->Right;
113 else if (T->Right == NULL)
114 T = T->Left;
115 free(TmpCell);
116 }
117
118 return T;
119 }
