Problem with inserting nodes on Binary trees

Discussion in 'C Programming' started by Blondeamon, Dec 24, 2007.

  1. Blondeamon

    Blondeamon Guest

    Ok i'll try to be brief. As part of one of my essays i thought of
    creating source code for implementation of a binary tree and its basic

    My code is both from books,lecture notes and googling but for some
    reason on the printing of the nodes using inOrder traversal only 2 or 3
    nodes are being printed.

    I will put my code here although i am sure that only few might actually
    comprehend what it is about because this subject needs good knowledge of
    all the tricks about inserting/deleting nodes from theory of Binary Trees.

    Exercise: Create code for a binary tree.The program reads the size of
    the tree N and then inserts N nodes with values between 1 and 30.000
    into the tree.
    You cant enter a node if it is not already on the tree,so you must
    search if it exists before entering it.

    Finally ,after having inserted all N nodes print them using InOrder

    Tips: My code works for the first 2 nodes...but doesnt
    print anything else.And i will bust my head open if i wont figure out why.

    I appreciate any help guys , this is a tough question and this is my
    first time on this forum.
    (seems very warm so far btw)

    Code (Text):
    #include <iostream>
    #include <cstdlib>
    #include <ctime>

    using namespace std;

    //the struct which represents the node
    struct tnode {
            struct tnode *left, *right;
            int key;

    void InOrder( tnode *x )
            if (x == 0) return;
            cout << x->key << " ";

    int main ()
            tnode *root = 0;
            int size, key2;
            int flag;

            cout << "\nPlease enter the size of the tree.  N: ";
            cin >> size;

            for (int i = 0; i < size; i++) {
                    key2 = 1 + rand() % 30000;  //creating random node key
    between 1-30.000
                    tnode *p = root;
                    tnode *q = 0 ;
                    flag = 0;

               //searching existing tree for node with that value

                    while((p != 0)&&(flag==0)) {
                            q = p;
                            if (p->key == key2) {
                                    flag = 1; //node with that key already
    exists -cant enter
                            } else if (p->key < key2) {
                                    p = p->left; //case 1: key smaller than root
                            } else {
                                    p = p->right; //case 2: key bigger than root

                      //creating new node with key2 as content
                    if (flag == 0) { //flag is 0 when that value didnt
    already exist on the tree
                            tnode *z = new tnode;
                            z->key = key2;
                            z->left = 0;
                            z->right = 0;    //creation of nw node that will
    take key2 as its value
                                   //and will have 2 NULL kids (left and right)

                            if (q == 0) {
                                    root = z;
                            //case of empty tree
                            //case handling about where the new node will be put
                            } else if (key2 > q->key) {
                                    q->right = z;
                            } else {
                                    q->left = z;

            //cout << "\nroot is : "<< root->key;          //not needed
    ,just for checking
        //the value of root
            cout << endl;
            cin >> size;
            return 0;
    Blondeamon, Dec 24, 2007
    1. Advertisements

  2. Blondeamon wrote:
    > [...]
    > Tips:

    This isn't a web forum, so I don't think BBcode is supposed to work here.

    Code (Text):
    #include <iostream>
    > #include <cstdlib>
    > #include <ctime>
    > using namespace std;[/color]

    It looks like C++ to me so I guess it's off-topic here.
    Nikos Chantziaras, Dec 24, 2007
    1. Advertisements

Want to reply to this thread or ask your own question?

It takes just 2 minutes to sign up (and it's free!). Just click the sign up button to choose a username and then you can ask your own questions on the forum.
Similar Threads
  1. asd
    Arnaud Berger
    May 23, 2005
  2. gavnosis
    Aug 2, 2003
  3. Blondeamon
    Nikos Chantziaras
    Dec 24, 2007
  4. cesarcesar

    Inserting Nodes between Nodes

    cesarcesar, Jan 21, 2008, in forum: XML
    Joseph Kesselman
    Jan 22, 2008
  5. jacob navia

    Binary search trees (AVL trees)

    jacob navia, Jan 3, 2010, in forum: C Programming
    Dann Corbit
    Jan 8, 2010

Share This Page