void push_history(char **args)
{
    int args_length = 0;
    for(int i = 0; args[i] != NULL; i++)
        args_length++;

    char ** hard_copy = new char*[args_length];

    for(int i = 0; i < args_length; i++)
        hard_copy[i] = args[i];


    vector_length++;
    hist.push_back(hard_copy);
}


//print history
void printHistory()
{
    int count = 0;
    string str_cat = "";

    if(vector_length <= 10)
    {
        for(int i = 0; i < vector_length; i++)
        {
            str_cat = "";
            for(int ii = 0; hist[i][ii] != NULL; ii++)
            {
                str_cat += hist[i][ii];
                str_cat += " ";
            }
            cout << (count+1) << "  " << str_cat <<  endl;
            count++;
        }
    }

    //more than 10 commands in history
    else
    {
        for(int i = vector_length - 10; i < vector_length; i++)
        {
            str_cat = "";
            for(int ii = 0; hist[i][ii] != NULL; ii++)
            {
                str_cat += hist[i][ii];
                str_cat += " ";
            }
            cout << (count+1) << "  " << str_cat <<  endl;
            count++;
        }
    }
}