개발이 하고 싶어요

import java.util.HashSet;
import java.util.Set;
import java.util.function.Function;
import java.util.stream.Collectors;

public class CountingDuplicates {
  public static int duplicateCount(String text) {
	  // Write your code here
	  return (int) text.toLowerCase().chars().mapToObj(x->(char) x)
	  .collect(Collectors.groupingBy(Function.identity(), Collectors.counting())).entrySet().stream()
	  .filter(x -> x.getValue() >1).count();
  }
  
  public static int duplicateCount2(String text) {
	    // Write your code here
	  	Set<Character> count = new HashSet<Character>();
	    text = text.toLowerCase();
	    for (char element : text.toCharArray()) {
	    	if(text.indexOf(element) != text.lastIndexOf(element)) count.add(element);
	    }
		return count.size();
  }
}