Can you give me some hints?

The program is to build a node tree , then print it out as follow format, can anyone give me some hints or any reference web site about doing this, thanks.

(the symbol '+' are spaces)
output :

0
++1
+++++11
++++++++111
++++++++++++1112
+++++++++++++++++11122 Mary
+++++++++++++++++11123 Jane
++++++++112
++++++++++++1121
+++++++++++++++++11211 John
+++++12
++++++++121
++++++++++++1213
+++++++++++++++++12131 Jack


Sorry, i 've just post it wrongly in C++ Forum

Which part are you having trouble with specifically?


Quzah.

INPUT : MARY 11122

this program is to build a tree (eahc node has 3 sons : left called 1, middle called 2, and right called 3. According to the input of id : 11122. First, build a root node, then build a left node(1). Secondly, build a left node again (1). Thirdly, build a left node (1) again. Forthly, build a middle node (2). Finally build a middle node (2) and save the name 'Mary' to this leaf node. So it match the id : 11122.

But in the below program , it can just build 2 levels node and how can it save 'Mary' to name during the recursion of BuildTree. Thanks for your help!!

Code:

---

//Build a tree
NodePtr BuildTree(NodePtr tree,char name[], int id)
{        NodePtr p, T =tree;
        int RightDigit;
        p = T;

        if ( id < 10 )
        {        if (id == 1)
                {        if (p->left == NULL)
                        {        p->left = maketree (name);
                                return (T);
                        }
                        else
                                p = p->left;
                }                       
                else if (id == 2)
                {        if (p->middle == NULL)
                        {        p->middle = maketree (name);
                                return (T);
                        }
                        else
                                p=p->middle;
                }
                else
                {        if (p->right == NULL)
                        {        p->right = maketree (name);
                                return (T);
                        }
                        else
                                p=p->right;
                }
        }
        else
        {        int LeftMostDigit;               
                LeftMostDigit = getLeftDigit(id); //11122->1
               
                while ( LeftMostDigit > 0 )
                {        if (LeftMostDigit == 1)
                        {        if (p->left == NULL)
                                {        p->left = maketree ("---");
                                        p = p->left;
                                        break;
                                }
                                else
                                        p = p->left;
                        }
                        else if (LeftMostDigit == 2)
                        {        if (p->middle == NULL)
                                {        p->middle = maketree ("---");
                                        p = p->middle;
                                        break;
                                }
                                else
                                        p = p->middle;
                        }                       
                        else
                        {        if (p->right == NULL)
                                {        p->right = maketree ("---");
                                        p = p->right;
                                        break;
                                }
                                else
                                        p = p->right;               
                        }
                }
        }
        RightDigit = getRightDigit(id); //11122->1122
        T = BuildTree(T, name, RightDigit);
        return (T);
}

---

Where's maketree()?

maketree code as below :

Code:

---

NodePtr maketree(char name[]) //create a new node.
{        NodePtr p;
        p= (NodePtr)LoggedMalloc(sizeof(struct node));
        p->name[SIZE] = name[SIZE];
        p->right = NULL;
                p->middle = NULL;
        p->left = NULL;
        return(p);
}

---

Code:

---

p->name[SIZE] = name[SIZE];

---

1 - SIZE is actually past the end of the array, if the array has SIZE elements.
2 - You cannot copy entire arrays this way. What this would do is copy the data in the single element 'name[SIZE]' to the element 'p->name[SIZE]', if in fact you had an element SIZE, which you don't, as noted in point 1.
3 - If you are trying to copy a string, assuming 'name' is a string, you'll want one of the string functions, such as strcpy.

Quzah.

You forgot to mention the casting of the malloc() clone.