how to do this recursive program?

[iamuser2007]

hi

int main(int argc, char *argv[]) 
{
    cout << "Enter a string: ";
    string input;
    getline(cin, input);

    vector<string> v = generate_subsets(input);
    for (int i = 0; i < v.size(); i++)
    cout << v[i] << endl;

    return 0;
}

[h3432]

Care to be more specific about what the problem is?

[iamuser2007]

i am getting error on the line 49 and cannot output the final result.

[firedraco]

And the error is?

[iamuser2007]

errors are

In function `std::vector<std::string, std::allocator<std::string> > generate_subsets(std::string)': 

invalid conversion from `const char' to `const char*' 

initializing argument 1 of `std::basic_string<_CharT, _Traits, _Alloc>::basic_string(const _CharT*, const _Alloc&) [with _CharT = char, _Traits = std::char_traits<char>, _Alloc = std::allocator<char>]' 

and also i don't understand exactly what to write in main fuction.