C Program for Binary Search Tree of Characters and Recursively in Postorder

1	-	-	#include<stdio.h>
2			#include<stdlib.h>
3			struct node
4			{
5			char data;
6			struct node *left;
7			struct node *right;
8			}*ptr;
9			struct node *searched,*max,*min;
10			struct node *deleted(struct node *ptr,char ele);
11			struct node *insert(struct node *ptr,char ele);
12			struct node *findmin(struct node *ptr);
13			struct node *findmax(struct node *ptr);
14			struct node *search(struct node *ptr,char ele);
15			void inorder(struct node *ptr);
16			void preorder(struct node *ptr);
17			void postorder(struct node *ptr);
18			void main()
19			{
20			int ch;
21			char ele;
22			ptr=NULL;
23			printf("\n ----Main Menu---");
24			printf("\n1.Insert \n2.Delete\n3.Search\n4.Inoredr\n5.Preorder\n6.Postorder\n7.Findmin\n8.Findmax\n9.Exit");
25			while(1)
26			{
27			printf("\nEnter ur choice : ");
28			scanf("%d",&ch);
29			switch(ch)
30			{
31			case 1:
32			printf("\nEnter an element to insert : ");
33			scanf("\n%c",&ele);
34			ptr=insert(ptr,ele);
35			break;
36			case 2: printf("\nEnter element to delete : ");
37			scanf("\n%c",&ele);
38			ptr=deleted(ptr,ele);
39			printf("\n Deleted Successfully");
40			break;
41			case 3: printf("\nEnter a element to search : ");
42			scanf("\n%c",&ele);
43			searched=search(ptr,ele);
44			if(searched==NULL)
45			printf("\nElement is not found");
46			else
47			printf("\nElement is found");
48			break;
49			case 4:
50			inorder(ptr);
51			break;
52			case 5: preorder(ptr);
53			break;
54			case 6: postorder(ptr);
55			break;
56			case 7: min=findmin(ptr);
57			if(min!=NULL)
58			printf("\n Minimum value is %c" ,min->data);
59			else
60			printf("\nTree is empty");
61			break;
62			case 8: max=findmax(ptr);
63			if(max!=NULL)
64			printf("\n Maximum value is %c ",max->data);
65			else
66			printf("\nTree is empty");
67			break;
68			case 9: exit(0);
69			default: printf("\n Wrong choice");
70			}
71			}
72			}
73			struct node *insert(struct node *ptr,char ele)
74			{
75			if(ptr==NULL)
76			{
77			ptr= (struct node *)malloc(sizeof(struct node));
78			ptr->data=ele;
79
80			ptr->left=ptr->right=NULL;
81			}
82			else if(ele<ptr->data)
83			ptr->left=insert(ptr->left,ele);
84			else if(ele>ptr->data)
85			ptr->right=insert(ptr->right,ele);
86			else
87			printf("\nElement exists");
88			return(ptr);
89			}
90			struct node *deleted(struct node *ptr,char ele)
91			{
92			struct node *tempmin,*temp;
93			if(ptr==NULL)
94			{
95			printf("\nTree is Empty");
96			return NULL;
97			}
98			else if(ele<ptr->data)
99			ptr->left=deleted(ptr->left,ele);
100			else if(ele>ptr->data)
101			ptr->right=deleted(ptr->right,ele);
102			else
103			{
104			if(ptr->left!=NULL && ptr->right!=NULL)
105			{
106			tempmin=findmin(ptr->right);
107			ptr->data=tempmin->data;
108			ptr->right=deleted(ptr->right,tempmin->data);
109			free(tempmin);
110			}
111			else
112			{
113			temp=ptr;
114			if(ptr->left==NULL)
115			ptr=ptr->right;
116			else if(ptr->right==NULL)
117			{
118			ptr=ptr->left;
119			free(temp);
120			}
121			}
122			}
123			return(ptr);
124			}
125			struct node *findmin(struct node *ptr)
126			{
127			if(ptr!=NULL)
128			{
129			while(ptr->left!=NULL)
130			ptr=ptr->left;
131			return(ptr);
132			}
133			else
134			return(NULL);
135			}
136			struct node *findmax(struct node *ptr)
137			{
138			if(ptr!=NULL)
139			{
140			while(ptr->right!=NULL)
141			ptr=ptr->right;
142			return(ptr);
143			}
144			else
145			return(NULL);
146			}
147			struct node *search(struct node *ptr,char ele)
148			{
149			if(ptr==NULL)
150			return NULL;
151			else
152			{
153			if(ele<ptr->data)
154			return(search(ptr->left,ele));
155			else if(ele>ptr->data)
156			return(search(ptr->right,ele));
157			else if(ele==ptr->data)
158			return(ptr);
159			else
160			return(NULL);
161			}
162			}
163			void inorder(struct node *ptr)
164			{
165			if(ptr==NULL)
166			return;
167			else
168			{
169			inorder(ptr->left);
170			printf("%c ",ptr->data);
171			inorder(ptr->right);
172			}
173			}
174			void preorder(struct node *ptr)
175			{
176			if(ptr==NULL)
177			return;
178			else
179			{
180			printf("%c ",ptr->data);
181			preorder(ptr->left);
182			preorder(ptr->right);
183			}
184			}
185			void postorder(struct node *ptr)
186			{
187			if(ptr==NULL)
188			return;
189			else
190			{
191			postorder(ptr->left);
192			postorder(ptr->right);
193			printf("%c ",ptr->data);
194			}
195			}
			OUTPUT:
			1.Insert
			2.Delete
			3.Search
			4.Inoredr
			5.Preorder
			6.Postorder
			7.Findmin
			8.Findmax
			9.Exit
			Enter ur choice : 1
			Enter an element to insert : C
			Enter ur choice : 1
			Enter an element to insert : A
			Enter ur choice : 1
			Enter an element to insert : B
			Enter ur choice : 1
			Enter an element to insert : E
			Enter ur choice : 1
			Enter an element to insert : F
			Enter ur choice : 1
			Enter an element to insert : D
			Enter ur choice : 4
			A B C D E F
			Enter ur choice : 5
			C A B E D F
			Enter ur choice : 6
			B A D F E C
			Enter ur choice : 2
			Enter element to delete : C
			Deleted Successfully
			Enter ur choice : 4
			A B D E F
			Enter ur choice : 5
			D A B E F
			Enter ur choice : 6
			B A F E D
			Enter ur choice : 7
			Minimum value is A
			Enter ur choice : 8
			Maximum value is F
			Enter ur choice : 3
			Enter a element to search : A
			Element is found
			Enter ur choice : 9