Editing a Node in a binary tree structure [closed] - c++

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I'm working on a code... almost finished but I'm stuck with one last thing,
I need to find a way to edit a client's info when the user wishes to.
this is my code... any one can tell me what's wrong please? :
#include <iostream>
#include <string>
#include <fstream>
using namespace std;
ifstream infile;
ofstream outfile;
struct INFO {
int id;
string name;
unsigned balance;
long phone;
};
class Node
{
public:
INFO data;
Node *left;
Node *right;
Node() {
data.id = 0;
data.name = "NULL";
data.phone = 0;
data.balance = 0;
}
Node(INFO a)
{
data = a;
left = 0;
right = 0;
}
};
class Tree
{
public:
Node *root;
INFO inf;
Node *zero;
Tree()
{
root = 0;
}
bool insert(INFO inf)
{
if (root == 0)
{
root = new Node(inf);
return true;
}
Node *p = root;
Node *q = root;
while (p != 0)
{
q = p;
if (p->data.id == inf.id)
return false;
if (p->data.id > inf.id)
p = p->left;
else
p = p->right;
}
if (inf.id < q->data.id)
q->left = new Node(inf);
else
q->right = new Node(inf);
return true;
}
bool searchid(Node *p, int y)
{
if (p != 0) {
if (p->data.id == y) {
cout << "ID: ";
cout << p->data.id << "\t";
cout << "Name: ";
cout << p->data.name << "\t";
cout << "Balance: ";
cout << p->data.balance << "\t";
cout << "Phone number: ";
cout << p->data.phone << endl;
cout << "_________________" << endl;
return true;
}
}
if (p->left != 0) {
if (searchid(p->left, y)) {
return true;
}
}
if (p->right != 0) {
if (searchid(p->right, y)) {
return true;
}
}
return false;
}
Node SAD(int id) {
Node *p = root;
if (p->data.id == id) {
Node *q = p;
return *p;
}
if (p->left != 0)
SAD(p->left->data.id);
if (p->right != 0)
SAD(p->right->data.id);
return *zero;
}
void edit(int q) {
Node p = SAD(q);
cout << "The ID is: " << p.data.id << endl;
cout << "The account owner: ";
cout << p.data.name << endl;
cout << "Do you want to edit the owner?(Y/N) ";
char x;
cin >> x;
if (x == 'Y' || x == 'y') {
string New;
cout << "Enter the new owner name: ";
cin >> New;
p.data.name = New;
}
cout << "The Balance in the account is: ";
cout << p.data.balance << endl;
cout << "Do you want to edit the balance?(Y/N) ";
cin >> x;
if (x == 'Y' || x == 'y') {
int New;
cout << "Enter the new Balance: ";
cin >> New;
p.data.balance = New;
}
cout << "The phone number is: ";
cout << p.data.phone << endl;
cout << "Do you want to edit the phone number?(Y/N) ";
cin >> x;
if (x == 'Y' || x == 'y') {
long New;
cout << "Enter the new phone number";
cin >> New;
p.data.phone = New;
}
cout << p.data.id << " " << p.data.name << " " << p.data.balance << " " << p.data.phone << endl;
insert(p.data);
}
void print(Node *p)
{
if (p != 0) {
cout << "ID: ";
cout << p->data.id << "\t";
cout << "Name: ";
cout << p->data.name << "\t";
cout << "Balance: ";
cout << p->data.balance << "\t";
cout << "Phone number: ";
cout << p->data.phone << endl;
cout << "_______________________________________________________________" << endl<<endl;
}
if (p->left != 0)
print(p->left);
if (p->right != 0)
print(p->right);
}
void store(Node *p)
{
if (p != 0) {
outfile << "ID: ";
outfile << p->data.id << " ";
outfile << "Name: ";
outfile << p->data.name << " ";
outfile << "Balance: ";
outfile << p->data.balance << " ";
outfile << "Phone number: ";
outfile << p->data.phone << endl;
outfile << "_______________________________________________________________" << endl;
}
if (p->left != 0)
store(p->left);
if (p->right != 0)
store(p->right);
}
bool searchname(Node *p, string x)
{
Node *q = root;
q = p;
while (p != 0) {
if (p->data.name == x) {
cout << "ID: " << p->data.id << "\t";
cout << "Name: " << p->data.name << "\t";
cout << "Balance: " << p->data.balance << "\t";
cout << "Phone number: " << p->data.phone << endl;
}
else {
}
}
}
};
void main()
{
outfile.open("clients.txt");
int opt;
Tree t;
int m = 1;
while (m != 0) {
cout << "Choose an option:" << endl << "1- To Add new clients." << endl << "2- To Display the clients." << endl << "3- To Store the clients in a Text Document." << endl << "4- To Search for a specific client through it's ID." << endl << "5- To Edit a specific client's information" << endl << "6- To Delete a specific client." <<endl<<"7- Exit."<< endl;
cin >> opt;
switch (opt) {
case 1:
int n;
cout << "Enter the amount of clients: ";
cin >> n;
INFO *arr;
arr = new INFO[n];
cout << "Enter the elements of the array: " << endl;
for (int i = 0; i < n; i++)
{
cout << "Client #" << i + 1 << endl << "-----------" << endl;
cout << "Enter the ID: ";
cin >> arr[i].id;
cout << "Enter the name of the client: ";
cin >> arr[i].name;
cout << "Enter the balance: ";
cin >> arr[i].balance;
cout << "Enter the phone number: ";
cin >> arr[i].phone;
t.insert(arr[i]);
}
break;
case 2:
t.print(t.root);
break;
case 3:
t.store(t.root);
cout << "Saved!" << endl << "in directory: C:/Users/Taiseer/Documents/Visual Studio 2015/Projects/ADS Project/ADS Project" << endl;
break;
case 4:
cout << endl;
int s;
cout << "What element do you want to search for? ";
cin >> s;
if (t.searchid(t.root, s) == false) {
cout << " Not here.... :( \n";
}
cout << endl;
break;
case 5:
char x;
cin >> x;
if (x == 'y' || x == 'Y') {
int id;
cout << "Enter the id you want to edit: ";
cin >> id;
t.edit(id);
}
else
return;
break;
case 6:
break;
case 7:
m = 0;
break;
default:
cout << "lol" << endl;
}
}
}

Answer 1

The problem is that Tree::SAD() returns the node that is being searched for by value. This means that in Tree::edit(), the following line:
Node p = SAD(q);
Gets a copy of the actual node. Anything changed in p is not changed in the actual Tree. At the end of edit(), you try to insert(p.data), but this does not do anything, because your implementation of insert() never overwrites already existing nodes.
One solution is to make SAD() return a pointer to the found node. This has the added benefit that you can return nullptr to signal the case where the searched for id does not exist. This can then be used in edit() to change the fields of the Node structure directly.