// "Replace Stream API chain with loop" "true"

import java.util.Arrays;
import java.util.Objects;

public class Main {
  String test(String[] strings) {
      for (String s : strings) {
          if (Objects.nonNull(s)) {
              if (!s.startsWith("xyz")) {
                  return "s";
              }
          }
      }
      return null;
  }
}