Hey guys,
Im implementing a binary tree in C and i add values one by one into the Binary Tree , Once i select the Function to display the minimum and Maximum values the Program Crashes , Please help me fix this , greatly appreciated. Thanks . this is my code.
#include<stdio.h>
#include<stdlib.h>
struct tree
{
int info;
struct tree *left;
struct tree *right;
};
*root = NULL;
struct tree *insert(struct tree *,int);
void inorder(struct tree *);
void postorder(struct tree *);
void preorder(struct tree *);
void min_max(struct tree *t);
struct tree *delet(struct tree *,int);
struct tree *search(struct tree *);
int main(void)
{
struct tree *root;
int choice, item,item_no;
root = NULL;
system("cls");
/* rear = NULL;*/
do
{
do
{
printf("\n \t 1. Insert in Binary Tree ");
printf("\n\t 2. Delete from Binary Tree ");
printf("\n\t 3. Inorder traversal of Binary tree");
printf("\n\t 4. Postorder traversal of Binary tree");
printf("\n\t 5. Preorder traversal of Binary tree");
printf("\n\t 6. Search and replace ");
printf("\n\t 7. Display Minimum And Maximum Values ");
printf("\n\t 8. Sort Binary Tree ");
printf("\n\t 9. Exit ");
printf("\n\t Enter choice : ");
scanf(" %d",&choice);
if(choice<1 || choice>7)
printf("\n Invalid choice - try again");
}while (choice<1 || choice>7);
switch(choice)
{
case 1:
printf("\n Enter new element: ");
scanf("%d", &item);
root= insert(root,item);
printf("\n root is %d",root->info);
printf("\n Inorder traversal of binary tree is : ");
inorder(root);
break;
case 2:
printf("\n Enter the element to be deleted : ");
scanf(" %d",&item_no);
root=delet(root,item_no);
inorder(root);
break;
case 3:
printf("\n Inorder traversal of binary tree is : ");
inorder(root);
break;
case 4:
printf("\n Postorder traversal of binary tree is : ");
postorder(root);
break;
case 5:
printf("\n Preorder traversal of binary tree is : ");
preorder(root);
break;
case 6:
printf("\n Search and replace operation in binary tree ");
root=search(root);
break;
case 7:
printf("\n Display Min And Max Values");
min_max(root);
break;
case 8:
printf("\n Search and replace operation in binary tree ");
root=search(root);
break;
default:
printf("\n End of program ");
} /* end of switch */
}while(choice !=7);
return(0);
}
struct tree *insert(struct tree *root, int x)
{
if(!root)
{
root=(struct tree*)malloc(sizeof(struct tree));
root->info = x;
root->left = NULL;
root->right = NULL;
return(root);
}
if(root->info > x)
root->left = insert(root->left,x);
else
{
if(root->info < x)
root->right = insert(root->right,x);
}
return(root);
}
void inorder(struct tree *root)
{
if(root != NULL)
{
inorder(root->left);
printf(" %d",root->info);
inorder(root->right);
}
return;
}
void postorder(struct tree *root)
{
if(root != NULL)
{
postorder(root->left);
postorder(root->right);
printf(" %d",root->info);
}
return;
}
void preorder(struct tree *root)
{
if(root != NULL)
{
printf(" %d",root->info);
preorder(root->left);
preorder(root->right);
}
return;
}
void min_max(struct tree *temp)
{
while (temp->left != NULL)
temp = temp->left;
printf("Minimum value = %d\n", temp->info);
temp = root;
while (temp->right != NULL)
temp = temp->right;
printf("Maximum value = %d\n", temp->info);
}
/* FUNCTION TO DELETE A NODE FROM A BINARY TREE */
struct tree *delet(struct tree *ptr,int x)
{
struct tree *p1,*p2;
if(!ptr)
{
printf("\n Node not found ");
return(ptr);
}
else
{
if(ptr->info < x)
{
ptr->right = delet(ptr->right,x);
/*return(ptr);*/
}
else if (ptr->info >x)
{
ptr->left=delet(ptr->left,x);
return ptr;
}
else /* no. 2 else */
{
if(ptr->info == x) /* no. 2 if */
{
if(ptr->left == ptr->right) /*i.e., a leaf node*/
{
free(ptr);
return(NULL);
}
else if(ptr->left==NULL) /* a right subtree */
{
p1=ptr->right;
free(ptr);
return p1;
}
else if(ptr->right==NULL) /* a left subtree */
{
p1=ptr->left;
free(ptr);
return p1;
}
else
{
p1=ptr->right;
p2=ptr->right;
while(p1->left != NULL)
p1=p1->left;
p1->left=ptr->left;
free(ptr);
return p2;
}
}/*end of no. 2 if */
}/* end of no. 2 else */
/* check which path to search for a given no. */
}
return(ptr);
}
/* function to search and replace an element in the binary tree */
struct tree *search(struct tree *root)
{
int no,i,ino;
struct tree *ptr;
ptr=root;
printf("\n Enter the element to be searched :");
scanf(" %d",&no);
fflush(stdin);
while(ptr)
{
if(no>ptr->info)
ptr=ptr->right;
else if(no<ptr->info)
ptr=ptr->left;
else
break;
}
if(ptr)
{
printf("\n Element %d which was searched is found and is = %d",no,ptr->info);
printf("\n Do you want replace it, press 1 for yes : ");
scanf(" %d",&i);
if(i==1)
{
printf("\n Enter new element :");
scanf(" %d",&ino);
ptr->info=ino;
}
else
printf("\n\t It's okay");
}
else
printf("\n Element %d does not exist in the binary tree",no);
return(root);
}
