#include <iostream>
#include <cstring>

using namespace std;

string work (string in_string)
{
    int len = in_string.length();

    for (int i = 0; i < len; i++)
    {
        if ((in_string[i] == ',') && (in_string[i + 1] != ' '))
        {
            in_string.replace(i, 1 , ", ");
            len++;
        }
    }
    return in_string;
}


int main()
{
    setlocale(0, "");

    string str1[] = "trolilo";
    string str2[] = "trolilo,2000";
    string str3[] = "";

    if ((work("trolilo") == "trolilo")
        && (work("trolilo,2000") == "trolilo, 2000")
        && (work("trolilo,2,0,0,0") == "trolilo, 2, 0, 0, 0")
        && (work("trolilo,2,0,0,0,") == "trolilo, 2, 0, 0, 0, ")
        && (work("") == ""))
        cout << "Программа работает верно\n";
    else
        cout << "Программа работает не верно\n";

    return 0;
}