修复只有两个节点的链表

crossoverJie · crossoverJie · commit 1776fc6b6b2b · 2018-01-04T12:42:49.000+08:00
diff --git a/src/main/java/com/crossoverjie/algorithm/LinkLoop.java b/src/main/java/com/crossoverjie/algorithm/LinkLoop.java
@@ -37,6 +37,9 @@ public boolean isLoop(Node node){
                 return true ;
             }
 
+            if (fast.next == null){
+                return false ;
+            }
             //slow走慢点  fast走快点
             slow = slow.next ;
             fast = fast.next.next ;
diff --git a/src/test/java/com/crossoverjie/algorithm/LinkLoopTest.java b/src/test/java/com/crossoverjie/algorithm/LinkLoopTest.java
@@ -42,4 +42,21 @@ public void isLoop2() throws Exception {
         Assert.assertEquals(loop,true);
     }
 
+    /**
+     * 无环
+     * @throws Exception
+     */
+    @Test
+    public void isLoop3() throws Exception {
+        LinkLoop.Node node2 = new LinkLoop.Node("2") ;
+        LinkLoop.Node node1 = new LinkLoop.Node("1") ;
+
+        node1.next = node2 ;
+
+
+        LinkLoop linkLoop = new LinkLoop() ;
+        boolean loop = linkLoop.isLoop(node1);
+        Assert.assertEquals(loop,false);
+    }
+
 }

Original file line number	Diff line number	Diff line change
`@@ -37,6 +37,9 @@ public boolean isLoop(Node node){`
`37`	`37`	`return true ;`
`38`	`38`	`}`
`39`	`39`
	`40`	`+ if (fast.next == null){`
	`41`	`+ return false ;`
	`42`	`+ }`
`40`	`43`	`//slow走慢点 fast走快点`
`41`	`44`	`slow = slow.next ;`
`42`	`45`	`fast = fast.next.next ;`