Book e.g.: Code printing garbage values instead of actual values
I have just started learning C/C++ and this is my first post to this forum.
This is the e.g which I am practicing from a book and I take no credit for it.
bst_adt.h
Code:
#include <stdbool.h>
#include <stdlib.h>
typedef struct node{
void* dataPtr;
struct node* left;
struct node* right;
} NODE;
typedef struct{
int count;
int (*compare) (void* argu1, void* argu2);
NODE* root;
} BST_TREE;
BST_TREE* BST_Create (int (*compare) (void* argu1, void* argu2));
//BST_TREE* BST_Destroy (BST_TREE* tree);
bool BST_Insert (BST_TREE* tree, void* dataPtr);
//bool BST_Delete (BST_TREE* tree, void* dltKey);
void* BST_Retrieve (BST_TREE* tree, void* keyPtr);
void BST_Traverse (BST_TREE* tree, void (*process)(void* dataPtr));
static NODE* _insert(BST_TREE* tree, NODE* root, NODE* newPtr);
static NODE* _delete(BST_TREE* tree, NODE* root, void* dataPtr, bool* success);
static void* _retrieve(BST_TREE* tree, void* dataPtr, NODE* root);
static NODE* _insert(BST_TREE* tree, NODE* root, NODE* newPtr);
static void* _retrieve(BST_TREE* tree, void* dataPtr, NODE* root);
static void _traverse(NODE* root, void (*process) (void* dataPtr));
BST_TREE* BST_Create(int (*compare) (void* argu1, void* argu2)){
BST_TREE* tree;
tree = (BST_TREE*) malloc (sizeof (BST_TREE));
if (tree){
tree->root = NULL;
tree->count = 0;
tree->compare = compare;
}
return tree;
}
bool BST_Insert(BST_TREE* tree, void* dataPtr){
NODE* newPtr;
newPtr = (NODE*)malloc(sizeof(NODE));
if (!newPtr)
return false;
newPtr->right = NULL;
newPtr->left = NULL;
newPtr->dataPtr = newPtr;
if (tree->count == 0)
tree->root = newPtr;
else
_insert(tree, tree->root, newPtr);
(tree->count)++;
}
NODE* _insert (BST_TREE* tree, NODE* root, NODE* newPtr){
if (!root)
return newPtr;
if (tree->compare(newPtr->dataPtr, root->dataPtr) < 0){
root->left = _insert(tree, root->left, newPtr);
return root;
} else {
root->right = _insert(tree, root->right, newPtr);
return root;
}
return root;
}
void* BST_Retrieve (BST_TREE* tree, void* keyPtr){
if (tree->root)
return _retrieve (tree, keyPtr, tree->root);
else
return NULL;
}
void* _retrieve(BST_TREE* tree, void* dataPtr, NODE* root){
if (root){
if (tree->compare(dataPtr, root->dataPtr) < 0)
return _retrieve(tree, dataPtr, root->left);
else if (tree->compare(dataPtr, root->dataPtr) > 0)
return _retrieve(tree, dataPtr, root->right);
else
return root->dataPtr;
} else {
return NULL;
}
}
void BST_Traverse(BST_TREE* tree, void (*process) (void* dataPtr)){
_traverse(tree->root, process);
return;
}
void _traverse(NODE* root, void (*process) (void* dataPtr)){
if (root){
_traverse(root->left, process);
process(root->dataPtr);
_traverse(root->right, process);
}
return;
}
bst_integer.c
Code:
#include <stdio.h>
#include <stdlib.h>
#include "bst_adt.h"
int compareInt (void* num1, void* num2);
void printBST (void* num1);
int main(void){
BST_TREE* BSTRoot;
int* dataPtr;
int dataIn = dataIn + 1;
printf("Begin BST Demonstration\n");
BSTRoot = BST_Create(compareInt);
printf("Enter a list of positive integers\n");
printf("Enter a negative number to stop.\n");
do{
printf("Enter a number:");
scanf("%d", &dataIn);
if (dataIn > -1){
dataPtr = (int*) malloc (sizeof (int));
if (!dataPtr){
printf("Memory overflow");
exit (100);
}
*dataPtr = dataIn;
BST_Insert (BSTRoot, dataPtr);
}
} while (dataIn > -1);
printf("\nBST contains:\n");
BST_Traverse(BSTRoot, printBST);
printf("\nEND BST Demonstration\n");
return 0;
}
int compareInt(void* num1, void* num2){
int key1;
int key2;
key1 = *(int*)num1;
key2 = *(int*)num2;
if (key1 < key2)
return -1;
if (key1 == key2)
return 0;
return +1;
}
void printBST(void* num1){
printf("%4d\n", *(int*)num1);
return;
}
Code when compiled and run prints garbage values instead of actual input values. Not sure what am I missing?
Code:
gcc -o bst_int bst_integer.c
./bst_int
Quote:
Begin BST Demonstration
Enter a list of positive integers
Enter a negative number to stop.
Enter a number:1
Enter a number:2
Enter a number:3
Enter a number:4
Enter a number:-1
BST contains:
817904016
817904064
817904112
817904160
END BST Demonstration
