[CodeEngn.com] Advance RCE Level 12

Mission...
Find the Username when the Serial of 11E0-FBB4-490D
(This problem has multiple answers, so post your answer on the messageboard in a private thread and we will verify it for you.)
Note : "Registered Successfully" must pop up for the serial.
(Difficulty : ★★☆☆☆)


Analysis...

Solution and Coding...
Reverse2L12.cpp
Copyright (C) 2011 3735943886

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.

Private Access Only...

Result...

Omake...
Attachments are 'KeyGen' of Advance RCE level 12
Please feel free to download and test it.
For testing purpose, you can use following values. (one of working Name and Serial)

Name : 3735943886
Serial : 1315-EBDF-490F

Reverse2L12_keygen.exe

(Compiled with Windows SDK)

//
// Reverse2L12_keygen.cpp - KeyGen of Advance RCE L12 (CodeEngn.com)
// Made by 3735943886
// License : GPL
//

#include <iostream>
#include <sstream>
#include <string>

using namespace std;

bool KeyGen(string UserName, string *Serial)
{
    stringstream AsciiBuf;
    unsigned __int32 i;

    Serial->clear();
    // Create ASCII (dec) string buffer of User Name
    for(i = 0; i < UserName.length(); i++)
    {
        AsciiBuf << (unsigned __int32)UserName[i];
    }

    // Extract substring from ASCII buffer
    Serial->assign(AsciiBuf.str());
    if(Serial->length() < 8)
    {
        // If Name is too short, Error
        return 0;
    }
    Serial->assign(Serial->substr(4, 4));

    // Calculate 2nd block
    AsciiBuf.str(Serial->c_str());
    AsciiBuf >> i;
    AsciiBuf.clear();
    i = -i;
    AsciiBuf.str("");
    AsciiBuf << uppercase << hex << (i & 0xffff);
    Serial->push_back('-');
    Serial->append(AsciiBuf.str());

    // Modify 1st block
    // Read 3rd byte and add 0x0e
    AsciiBuf.str("");
    AsciiBuf << uppercase << hex << ((unsigned __int32)Serial->at(2) - '0' + 0x0e);
    // Replace it
    Serial->replace(Serial->find(Serial->at(2)), 1, AsciiBuf.str());

    // Calculated 3rd block
    AsciiBuf.str("");
    AsciiBuf << dec << (unsigned __int32)Serial->at(0);
    // StrCat [401F6C] =  0x30 = '0'
    AsciiBuf << "0";
    // Add Name Length + 0x05
    AsciiBuf << uppercase << hex << UserName.length() + 5;
    Serial->push_back('-');
    Serial->append(AsciiBuf.str(), 0, 4);

    if(Serial->at(4) != '-')
        Serial->erase(4, 1);
    return 1;
}

int main()
{
    string UserName, Serial;

    cout << endl << "Reverse2L12_keygen.cpp - KeyGen of Advance RCE L12 (CodeEngn.com)"
        << endl << "Made by 3735943886" << endl << "License : GPL" << endl << endl;

    cout << "User Name : "; cin >> UserName;

    if(KeyGen(UserName, &Serial))
    {
        cout << endl << "Serial : " << Serial << endl;
        return 1;
    }
    else
    {
        cout << endl << "Run-time error '13'." << endl << endl << "Type mismatch" << endl;
        return 0;
    }
}