সম্পাদনা
import java.util.Collection; import java.util.HashMap; import java.util.Map; public class Main { public static void main(String[] args) { Map<String, String> user = new HashMap<>(); user.put("নাম", "মোঃ আরিফ"); user.put("দেশ", "বাংলাদেশ"); Collection<String> result = user.keySet(); System.out.println(result); } }
পূর্বরূপ
