Thread: C++ BST segmentation fault

Hi,

I am trying to build a BST. I have so far this code and I must have made a mistake somewhere with the pointers, but I could not figure out where. So when I run it it says: "Segmentation fault (core dumped).

Here is the code:

Code:

//BTree#include <iostream>
using namespace std;


//BTree struct
struct BTree{
    int data;
    BTree* left;
    BTree* right;
};


//BTree new node
BTree* BTree_NewNode(int inputData){ //inputData = new entry in console
    BTree* node=new BTree;
    node->data=inputData;
    node->left=NULL;
    node->right=NULL;


    return(node);
};//BTree new node end


BTree* BTree_Insert(BTree* node, int inputData){
    if(node==NULL){
        return(BTree_NewNode(inputData));
    }else{
        if(inputData<=(node->data)){
            node->left=BTree_Insert(node->left,inputData);
        }else{
            node->right=BTree_Insert(node->right,inputData);
        }


        return(node); //else statemnet return
    }
};//BTree_Insert end


//Print out BTree
void BTree_Print(BTree* node){
    if((node->left)==NULL && (node->right)==NULL){
        return;
    }else{
        if((node->left)!=NULL){
            BTree_Print(node->left);
            cout<<"Data: "<<node->data<<endl;
        }
        else{
            BTree_Print(node->right);
            cout<<"Data: "<<node->data<<endl;
        }
    }
}//end BTree_Print()


int main(){
    BTree* root;
    BTree_Insert(root,5);
    BTree_Insert(root,2);
    BTree_Insert(root,7);
    BTree_Insert(root,8);
    BTree_Insert(root,1);


    BTree_Print(root);


    return 0;//main return
}//main() end

Originally Posted by Roland Kajatin

Code:

int main(){
    BTree* root;
    BTree_Insert(root,5);
    BTree_Insert(root,2);
    BTree_Insert(root,7);
    BTree_Insert(root,8);
    BTree_Insert(root,1);


    BTree_Print(root);


    return 0;//main return
}//main() end

EDIT to:

Code:

int main(){
    BTree* root=BTree_NewNode(5);
    BTree_Insert(root,4);
    BTree_Insert(root,8);
    BTree_Insert(root,6);
    BTree_Insert(root,1);


    BTree_Print(root);


    return 0;//main return
}//main() end

So this way it works to some extent. Still it only displays some of the values..

(I'm having a deja-vu here)
you code is terribly C-like. all of the functions you wrote should be some member functions. you should have a "Tree" class which inserts "Node" objects. both "Tree" and "Node" should have constructors and destructors.