#include <iostream>
#include <iomanip>
#include <cmath>
#include <string>

using namespace std;

int main()
{

    char input;
    cout << "Zadej cislo ve dvojkove soustave:" << endl;

        while (cin.get(input)){
            if (input='/n') cout << "Nespravny vstup." << break;
            if (input!='1' || input!='0') cout << "Nespravny vstup." << break;
            else cout << "b" << endl;

}


    return 0;
}