Update README.md

johnA1331 · web-flow · commit 5093997ca5fd · 2021-03-03T20:43:31.000+08:00
diff --git a/core-java-modules/core-java-collections-4/README.md b/core-java-modules/core-java-collections-4/README.md
@@ -5,3 +5,4 @@
 ### Relevant Articles: 
 
 - [ArrayList vs. LinkedList vs. HashMap in Java](https://www.baeldung.com/java-arraylist-vs-linkedlist-vs-hashmap)
+- [Java Deque vs. Stack](https://www.baeldung.com/java-deque-vs-stack)

Original file line number	Diff line number	Diff line change
`@@ -5,3 +5,4 @@`
`5`	`5`	`### Relevant Articles:`
`6`	`6`
`7`	`7`	`- [ArrayList vs. LinkedList vs. HashMap in Java](https://www.baeldung.com/java-arraylist-vs-linkedlist-vs-hashmap)`
	`8`	`+- [Java Deque vs. Stack](https://www.baeldung.com/java-deque-vs-stack)`