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POC++ array of pointers returns the same value for each element
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  1. POC++ array of pointers returns the same value for each element
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    copied!<p>I wrote a simplified version of the code I'm working on to illustrate a problem I'm having. I think something is wrong in <code>main()</code> that causes the <code>showUsers()</code> method to output the same Login/Password combo for every element (always the last one added).</p> <h3>Here is my code:</h3> <pre><code>#include &lt;iostream&gt; using namespace std; //============================================================================= class AccountInfo { private: char* _username; char* _password; public: AccountInfo(); AccountInfo(char* username, char* password); ~AccountInfo(); void setUsername(char* username); void setPassword(char* password); char* getUsername(); char* getPassword(); friend ostream&amp; operator&lt;&lt;(ostream&amp; out, AccountInfo&amp; x) { out &lt;&lt; "Login: " &lt;&lt; x.getUsername() &lt;&lt; endl &lt;&lt; "Password: " &lt;&lt; x.getPassword() &lt;&lt; endl; return out; } }; AccountInfo::AccountInfo() { _username = ""; _password = ""; } AccountInfo::AccountInfo(char* username, char* password) { _username = username; _password = password; } void AccountInfo::setUsername(char* username) { _username = username; } void AccountInfo::setPassword(char* password) { _password = password; } char* AccountInfo::getUsername() { return _username; } char* AccountInfo::getPassword() { return _password; } //============================================================================= class UsersDB { private: int _size; AccountInfo* _accounts[200]; public: UsersDB(); ~UsersDB(); int getSize(); void addUser(AccountInfo* newUser); void showUsers(); }; UsersDB::UsersDB() { _size = 0; } UsersDB::~UsersDB() { delete[] _accounts; } int UsersDB::getSize() { return _size; } void UsersDB::addUser(AccountInfo* newUser) { _accounts[_size] = newUser; _size++; } void UsersDB::showUsers() { for (int i = 0; i &lt; _size; i++) { cout &lt;&lt; *_accounts[i] &lt;&lt; endl; } } //---------------------------------------------------------emptyString function void emptyString(char* token, int size) { for (int i=0; i &lt; size; i++) token[i] = '\0'; } //----------------------------------------------------------copyString function void copyString (char* from, char* to, int size) { to = new char[size+1]; for (int i=0; i &lt; size; i++) to[i] = from[i]; to[size] = '\0'; } //--------------------------------------------------------getNextToken function int getNextToken(char* buffer, char* token, int startPos, int bufSize, int tokenSize, char delimeter) { int i, j; emptyString (token, tokenSize); i = startPos; j = 0; while ((buffer[i] == ' ') &amp;&amp; (i &lt; bufSize)) i++; //skipblanks if (i &lt; 256) { while ((buffer[i] != delimeter) &amp;&amp; (i &lt; 256) &amp;&amp; (j &lt; tokenSize)) token[j++] = buffer[i++]; } return i; } //============================================================================= int main() { char buffer[256]; char userLoginName[9]; char password[17]; int i, j, k; char flag[3];; char command[11]; char blank = ' '; UsersDB* users = new UsersDB(); AccountInfo* tempAccount; while (!cin.eof()) { //while end of line is not reached cin.getline(buffer, 256); k = getNextToken(buffer, command, 0, 256, 10, blank); if (command[0] == 'a') { tempAccount = new AccountInfo(); k = getNextToken(buffer, userLoginName, k, 256, 8, blank); (*tempAccount).setUsername(userLoginName); k = getNextToken(buffer, flag, k, 256, 2, blank); if (flag[1] == 'p') { k = getNextToken(buffer, password, k, 256, 16, blank); (*tempAccount).setPassword(password); } cout &lt;&lt; *tempAccount &lt;&lt; endl; (*users).addUser(tempAccount); } else if (command[0] == 's') { (*users).showUsers(); } else cout &lt;&lt; "Command not found." &lt;&lt; endl; } return 0; } </code></pre> <h3>The output looks like this:</h3> <pre>=============================================================================== >adduser bob -p password1 Login: bob Password: password1 >adduser jack -p mypassword Login: jack Password: mypassword >adduser jill -p pass1234 Login: jill Password: pass1234 >showusers Login: jill Password: pass1234 Login: jill Password: pass1234 Login: jill Password: pass1234 =============================================================================== </pre> <h3>The output SHOULD look like this:</h3> <pre>=============================================================================== >adduser bob -p password1 Login: bob Password: password1 >adduser jack -p mypassword Login: jack Password: mypassword >adduser jill -p pass1234 Login: jill Password: pass1234 >showusers Login: bob Password: password1 Login: jack Password: mypassword Login: jill Password: pass1234 =============================================================================== </pre> <p>Note: When I alter <code>main()</code> (by passing the info directly instead of getting it from the console using <code>cin</code>) to look like this:</p> <pre>//============================================================================= int main() { UsersDB* users = new UsersDB(); AccountInfo* tempAccount; tempAccount = new AccountInfo("jack", "mypassword"); (*users).addUser(tempAccount); tempAccount = new AccountInfo("jill", "pass1234"); (*users).addUser(tempAccount); (*users).showUsers(); return 0; }</pre> <p>...I get the desired output.</p> <p>Thanks a lot.</p>
 

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