add queue and stack

longcloud · longcloud · commit ad1d702c1f48 · 2017-02-25T21:43:07.000+08:00
diff --git a/group03/619224754/src/com/coding/basic/Queue.java b/group03/619224754/src/com/coding/basic/Queue.java
@@ -2,18 +2,22 @@
 
 public class Queue {
 	
-	public void enQueue(Object o){		
+	private LinkedList list = new LinkedList();
+	
+	public void enQueue(Object o){	
+		list.addLast(o);
 	}
 	
 	public Object deQueue(){
-		return null;
+		Object ret = list.removeFirst();
+		return ret;
 	}
 	
 	public boolean isEmpty(){
-		return false;
+		return list.size() == 0;
 	}
 	
 	public int size(){
-		return -1;
+		return list.size();
 	}
 }
diff --git a/group03/619224754/src/com/coding/basic/Stack.java b/group03/619224754/src/com/coding/basic/Stack.java
@@ -4,19 +4,22 @@ public class Stack {
 	private ArrayList elementData = new ArrayList();
 	
 	public void push(Object o){		
+		this.elementData.add(o);
 	}
 	
 	public Object pop(){
-		return null;
+		Object ret = this.elementData.remove(this.elementData.size() - 1);
+		return ret;
 	}
 	
 	public Object peek(){
+		Object ret = this.elementData.get(this.elementData.size() - 1);
 		return null;
 	}
 	public boolean isEmpty(){
-		return false;
+		return this.elementData.size() == 0;
 	}
 	public int size(){
-		return -1;
+		return this.elementData.size();
 	}
 }

Original file line number	Diff line number	Diff line change
`@@ -2,18 +2,22 @@`
`2`	`2`
`3`	`3`	`public class Queue {`
`4`	`4`
`5`		`- public void enQueue(Object o){`
	`5`	`+ private LinkedList list = new LinkedList();`
	`6`	`+`
	`7`	`+ public void enQueue(Object o){`
	`8`	`+ list.addLast(o);`
`6`	`9`	`}`
`7`	`10`
`8`	`11`	`public Object deQueue(){`
`9`		`- return null;`
	`12`	`+ Object ret = list.removeFirst();`
	`13`	`+ return ret;`
`10`	`14`	`}`
`11`	`15`
`12`	`16`	`public boolean isEmpty(){`
`13`		`- return false;`
	`17`	`+ return list.size() == 0;`
`14`	`18`	`}`
`15`	`19`
`16`	`20`	`public int size(){`
`17`		`- return -1;`
	`21`	`+ return list.size();`
`18`	`22`	`}`
`19`	`23`	`}`
Original file line number	Diff line number	Diff line change
`@@ -4,19 +4,22 @@ public class Stack {`
`4`	`4`	`private ArrayList elementData = new ArrayList();`
`5`	`5`
`6`	`6`	`public void push(Object o){`
	`7`	`+ this.elementData.add(o);`
`7`	`8`	`}`
`8`	`9`
`9`	`10`	`public Object pop(){`
`10`		`- return null;`
	`11`	`+ Object ret = this.elementData.remove(this.elementData.size() - 1);`
	`12`	`+ return ret;`
`11`	`13`	`}`
`12`	`14`
`13`	`15`	`public Object peek(){`
	`16`	`+ Object ret = this.elementData.get(this.elementData.size() - 1);`
`14`	`17`	`return null;`
`15`	`18`	`}`
`16`	`19`	`public boolean isEmpty(){`
`17`		`- return false;`
	`20`	`+ return this.elementData.size() == 0;`
`18`	`21`	`}`
`19`	`22`	`public int size(){`
`20`		`- return -1;`
	`23`	`+ return this.elementData.size();`
`21`	`24`	`}`
`22`	`25`	`}`