完成数据结构作业

group17/785396327/4.23/queue/QueueWithTwoStacks.java

@@ -16,27 +16,39 @@ public QueueWithTwoStacks() {
     }
 
 
-
-
     public boolean isEmpty() {
-        return false;
+        return stack1.size() == 0;
     }
 
 
-
     public int size() {
-        return -1;
+        return stack1.size();
     }
 
 
-
     public void enQueue(E item) {
-
+        Stack<E> temp = new Stack<E>();
+        stack1.push(item);
+        while (!stack2.isEmpty())
+            temp.push(stack2.pop());
+        temp.push(item);
+        while (!temp.isEmpty())
+            stack2.push(temp.pop());
     }
 
     public E deQueue() {
-        return null;
+        Stack<E> temp = new Stack<E>();
+        E ele = stack2.pop();
+        while (!stack1.isEmpty())
+            temp.push(stack1.pop());
+        temp.pop();
+        while (!temp.isEmpty())
+            stack1.push(temp.pop());
+        return ele;
     }
 
-
+    @Override
+    public String toString() {
+        return stack1.toString() + "\n" + stack2.toString();
+    }
 }

group17/785396327/4.23/queue/QueueWithTwoStacksTest.java

@@ -0,0 +1,37 @@
+package queue;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+/**
+ * Created by gongxun on 2017/4/26.
+ */
+public class QueueWithTwoStacksTest {
+
+    private QueueWithTwoStacks queue;
+
+    @Before
+    public void startUp() {
+        queue = new QueueWithTwoStacks();
+        queue.enQueue(1);
+        queue.enQueue(2);
+        queue.enQueue(3);
+    }
+
+    @After
+    public void tearDown() {
+
+    }
+
+    @Test
+    public void enQueueTest() {
+        System.out.println(queue);
+    }
+
+    @Test
+    public void deQueueTest() {
+        queue.deQueue();
+        System.out.println(queue);
+    }
+}