Lambda in constructor

#include <numeric>
#include <iostream>
#include <string>
#include <set>
#include <vector>
using namespace std;

class SearchServer
{
public:

    explicit SearchServer(const string& str) {

        cout << "String "s << str << " has been converted to a set of stop words"s << endl;

    }
    template <typename StringCollection>
    explicit SearchServer(const StringCollection& splitted_string) : SearchServer([splitted_string]() -> string {return accumulate(splitted_string.begin(), splitted_string.end(), string{});})
    {
        cout << "Container has been converted to a string and sent to constructor"s << endl;
    }
};

int main() {

    SearchServer ss1("one two three"s);
    vector<string> in_v = {"four"s, "five"s, "six"s};
    SearchServer ss2(in_v);

}