Convert to ASCII

#include <iostream>
#include <stdlib.h>
#include <dirent.h>
#include <sstream>
#include <string>
#include <fstream>

// Função para concatenar as variaveis
string concatenate(std::string const& name, int i)
{
    stringstream s;
    s << name << i;
    return s.str();
}

string convertToASCII(string letter)
{
    string result = "";
    for (int i = 0; i < letter.length(); i++)
    {
        char x = letter.at(i);
        if (int(x)<10 || int(x)==0)
            result = result + "00";
        if (int(x)<100 && int(x)>9)
            result = result + "0";
        result = concatenate(result, int(x));
    }
    return result;
}

int main()
{
    cout << "-" << convertToASCII("teste") << "-";
    return 0;
}