3.26

#include <iostream>
#include <sstream>
#include <string>
using namespace std;

int main() {
    string firstName, middleName, lastName;
    string fullName;
    
    getline(cin, fullName);

    stringstream ss(fullName);

    ss >> firstName >> middleName >> lastName;

    if (!lastName.empty()) {
        cout << lastName << ", " << firstName[0] << "." << middleName[0] << "." << endl;
    } 
    else {
        lastName = middleName;  // Handle two-word names
        cout << lastName << ", " << firstName[0] << "." << endl;
    }
    
    return 0;
}