#include <iostream>
#include <string>
using namespace std;
 
void generuj_permutacje(string zrodlo, string tworzacy)
{
    if(zrodlo.length() == 0)
    {
        cout << tworzacy << endl;
    }
    else
        for (int i = 0; i < zrodlo.length(); i++)
        {
            string noweZrodlo = zrodlo;
            string nowyTworzacy = tworzacy + zrodlo[i];
            noweZrodlo.erase(i, 1);
            generuj_permutacje(noweZrodlo, nowyTworzacy);
        }
}
 
int main()
{
    string zrodlo = "abcd";
    string tworzacy = "";
    generuj_permutacje(zrodlo, tworzacy);
}

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