From bce0d47f953bde453b1a014ccfd61905cffdd4d4 Mon Sep 17 00:00:00 2001
From: Leijurv <leijurv@gmail.com>
Date: Mon, 20 Mar 2023 23:58:25 -0700
Subject: [PATCH] tweak for older version of fastutil

---
 src/main/java/com/github/btrekkie/connectivity/ConnGraph.java | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/src/main/java/com/github/btrekkie/connectivity/ConnGraph.java b/src/main/java/com/github/btrekkie/connectivity/ConnGraph.java
index 2a813153f..f10848f3c 100644
--- a/src/main/java/com/github/btrekkie/connectivity/ConnGraph.java
+++ b/src/main/java/com/github/btrekkie/connectivity/ConnGraph.java
@@ -4,8 +4,6 @@ import it.unimi.dsi.fastutil.longs.Long2ObjectOpenHashMap;
 import it.unimi.dsi.fastutil.longs.LongSet;
 import it.unimi.dsi.fastutil.longs.LongSets;
 
-import java.util.*;
-
 /**
  * Implements an undirected graph with dynamic connectivity. It supports adding and removing edges and determining
  * whether two vertices are connected - whether there is a path between them. Adding and removing edges take O(log^2 N)
@@ -924,7 +922,7 @@ public class ConnGraph {
         if (info != null) {
             return info.edges.keySet();
         } else {
-            return LongSets.emptySet();
+            return LongSets.EMPTY_SET;
         }
     }