diff --git a/group27/425044891/src/com/coding/basic/ArrayList.java b/group27/425044891/src/com/coding/basic/ArrayList.java
new file mode 100644
index 0000000000..929a41661c
--- /dev/null
+++ b/group27/425044891/src/com/coding/basic/ArrayList.java
@@ -0,0 +1,97 @@
+package com.coding.basic;
+
+/**
+ * ArrayList
+ * 
+ * @author Guang
+ * @date 2017年3月12日 下午1:55:47
+ */
+public class ArrayList implements List {
+
+	/**
+	 * 数组中元素个数
+	 */
+	private int size = 0;
+
+	/**
+	 * 数组
+	 */
+	private Object[] elementData = new Object[100];
+
+	public void add(Object o) {
+		if (size >= 100 || size < 0) {
+			throw new IndexOutOfBoundsException("越界.");
+		}
+		if (null == o) {
+			return;
+		}
+		elementData[size] = o;
+		size++;
+	}
+
+	public void add(int index, Object o) {
+		checkRangeForAdd(index);
+		if (null == o) {
+			return;
+		}
+		for (int i = size; i > index; i--) {
+			elementData[i] = elementData[i - 1];
+		}
+		elementData[index] = o;
+		size++;
+	}
+
+	private void checkRangeForAdd(int index) {
+		if (index < 0 || index > size) {
+			throw new IndexOutOfBoundsException("越界.");
+		}
+	}
+
+	private void checkRangeForGet(int index) {
+		if (index < 0 || index >= size) {
+			throw new IndexOutOfBoundsException("越界.");
+		}
+	}
+
+	public Object get(int index) {
+		checkRangeForGet(index);
+		return elementData[index];
+	}
+
+	/**
+	 * 移除第index位置的元素，后续元素前移
+	 */
+	public Object remove(int index) {
+		checkRangeForGet(index);
+		int i = index;
+		Object o = elementData[index];
+		for (; i < size - 1; i++) {
+			elementData[i] = elementData[i + 1];
+		}
+		elementData[i] = null;
+		size--;
+		return o;
+	}
+
+	public int size() {
+		return size;
+	}
+
+	public Iterator iterator() {
+		return new Iterator() {
+			int index = 0;
+			@Override
+			public Object next() {
+				checkRangeForGet(index);
+				Object o = elementData[index];
+				index++;
+				return o;
+			}
+
+			@Override
+			public boolean hasNext() {
+				return index < size && index >= 0;
+			}
+		};
+	}
+}
\ No newline at end of file
diff --git a/group27/425044891/src/com/coding/basic/BinaryTreeNode.java b/group27/425044891/src/com/coding/basic/BinaryTreeNode.java
new file mode 100644
index 0000000000..c702b191e4
--- /dev/null
+++ b/group27/425044891/src/com/coding/basic/BinaryTreeNode.java
@@ -0,0 +1,41 @@
+package com.coding.basic;
+
+public class BinaryTreeNode<T extends Comparable<T>> {
+
+	private T data;
+	private BinaryTreeNode<T> left;
+	private BinaryTreeNode<T> right;
+
+	public T getData() {
+		return data;
+	}
+
+	public void setData(T data) {
+		this.data = data;
+	}
+
+	public BinaryTreeNode<T> getLeft() {
+		return left;
+	}
+
+	public void setLeft(BinaryTreeNode<T> left) {
+		this.left = left;
+	}
+
+	public BinaryTreeNode<T> getRight() {
+		return right;
+	}
+
+	public void setRight(BinaryTreeNode<T> right) {
+		this.right = right;
+	}
+
+	public BinaryTreeNode<T> insert(T o) {
+		if (o.compareTo(data) <= 0) {
+			return getLeft().insert(o);
+		} else {
+			return getRight().insert(o);
+		}
+	}
+
+}
\ No newline at end of file
diff --git a/group27/425044891/src/com/coding/basic/Iterator.java b/group27/425044891/src/com/coding/basic/Iterator.java
new file mode 100644
index 0000000000..de308cef25
--- /dev/null
+++ b/group27/425044891/src/com/coding/basic/Iterator.java
@@ -0,0 +1,6 @@
+package com.coding.basic;
+public interface Iterator {
+	public boolean hasNext();
+	public Object next();
+
+}
\ No newline at end of file
diff --git a/group27/425044891/src/com/coding/basic/LinkedList.java b/group27/425044891/src/com/coding/basic/LinkedList.java
new file mode 100644
index 0000000000..0c8520c62e
--- /dev/null
+++ b/group27/425044891/src/com/coding/basic/LinkedList.java
@@ -0,0 +1,274 @@
+package com.coding.basic;
+
+public class LinkedList implements List {
+
+	private Node head = null;
+
+	private int size = 0;
+
+	public LinkedList() {
+		this.head = new Node();
+		this.head.next = null;
+		this.head.data = null;
+		this.size = 0;
+	}
+
+	public void add(Object o) {
+		if (null == o) {
+			return;
+		}
+		Node next = new Node();
+		next.data = o;
+		next.next = null;
+
+		/**
+		 * 寻找尾部节点
+		 */
+		Node p = head;
+		while (p.next != null) {
+			p = p.next;
+		}
+		p.next = next;
+		size++;
+	}
+
+	public void add(int index, Object o) {
+		if (index < 0 || index > size) {
+			throw new IndexOutOfBoundsException();
+		}
+		if (null == o) {
+			return;
+		}
+		Node next = new Node();
+		next.data = o;
+		next.next = null;
+
+		Node p = head.next;
+		Node pre = head;
+		int pos = 0;
+		while (p != null && pos < index) {
+			pre = p;
+			p = p.next;
+			pos++;
+		}
+		next.next = p;
+		pre.next = next;
+		size++;
+	}
+
+	public Object get(int index) {
+		if (index < 0 || index >= size) {
+			throw new IndexOutOfBoundsException();
+		}
+		Node p = head.next;
+		int pos = 0;
+		while (p != null && pos < index) {
+			p = p.next;
+			pos++;
+		}
+		return p == null ? null : p.data;
+	}
+
+	public Object remove(int index) {
+		if (index < 0 || index >= size) {
+			throw new IndexOutOfBoundsException();
+		}
+		Node p = head.next;
+		Node pre = p;
+		int pos = 0;
+		while (p != null && pos < index) {
+			pre = p;
+			p = p.next;
+			pos++;
+		}
+		Object o = p.data;
+		pre.next = p.next;
+		size--;
+		return o;
+	}
+
+	public int size() {
+		return size;
+	}
+
+	public void addFirst(Object o) {
+		if (null == o) {
+			return;
+		}
+		Node next = new Node();
+		next.next = null;
+		next.data = o;
+
+		next.next = head.next;
+		head.next = next;
+		size++;
+	}
+
+	public void addLast(Object o) {
+		if (null == o) {
+			return;
+		}
+		Node p = head;
+		while (p.next != null) {
+			p = p.next;
+		}
+
+		Node next = new Node();
+		next.data = o;
+		next.next = null;
+
+		p.next = next;
+		size++;
+	}
+
+	public Object removeFirst() {
+		if (size <= 0) {
+			throw new IndexOutOfBoundsException();
+		}
+		Node p = head.next;
+		Object o = p.data;
+
+		head.next = p.next;
+		size--;
+		return o;
+	}
+
+	public Object removeLast() {
+		if (size <= 0) {
+			throw new IndexOutOfBoundsException();
+		}
+		Node p = head.next;
+		Node pre = head;
+		while (p.next != null) {
+			pre = p;
+			p = p.next;
+		}
+		Object o = p.data;
+		pre.next = p.next;
+		size--;
+		return o;
+	}
+
+	public Iterator iterator() {
+		return new Iterator() {
+			Node current = head;
+
+			@Override
+			public Object next() {
+				Object o = current.next.data;
+				current = current.next;
+				return o;
+			}
+
+			@Override
+			public boolean hasNext() {
+				return current.next != null;
+			}
+		};
+	}
+
+	private static class Node {
+		Object data;
+		Node next;
+	}
+
+	/**
+	 * 把该链表逆置 例如链表为 3->7->10 , 逆置后变为 10->7->3
+	 */
+	public void reverse() {
+		Node p = head.next.next;
+		Node pre = head.next;
+		pre.next = null;
+		while (p != null) {
+			Node pp = p.next;
+			p.next = pre;
+			pre = p;
+			p = pp;
+		}
+		head.next = pre;
+		// --- --- ---
+	}
+
+	/**
+	 * 删除一个单链表的前半部分 例如：list = 2->5->7->8 , 删除以后的值为 7->8 如果list = 2->5->7->8->10
+	 * ,删除以后的值为7,8,10
+	 * 
+	 */
+	public void removeFirstHalf() {
+		
+	}
+
+	/**
+	 * 从第i个元素开始， 删除length 个元素 ， 注意i从0开始
+	 * 
+	 * @param i
+	 * @param length
+	 */
+	public void remove(int i, int length) {
+
+	}
+
+	/**
+	 * 假定当前链表和listB均包含已升序排列的整数 从当前链表中取出那些listB所指定的元素 例如当前链表 =
+	 * 11->101->201->301->401->501->601->701 listB = 1->3->4->6
+	 * 返回的结果应该是[101,301,401,601]
+	 * 
+	 * @param list
+	 */
+	public int[] getElements(LinkedList list) {
+		return null;
+	}
+
+	/**
+	 * 已知链表中的元素以值递增有序排列，并以单链表作存储结构。 从当前链表中中删除在listB中出现的元素
+	 * 
+	 * @param list
+	 */
+
+	public void subtract(LinkedList list) {
+
+	}
+
+	/**
+	 * 已知当前链表中的元素以值递增有序排列，并以单链表作存储结构。 删除表中所有值相同的多余元素（使得操作后的线性表中所有元素的值均不相同）
+	 */
+	public void removeDuplicateValues() {
+
+	}
+
+	/**
+	 * 已知链表中的元素以值递增有序排列，并以单链表作存储结构。 试写一高效的算法，删除表中所有值大于min且小于max的元素（若表中存在这样的元素）
+	 * 
+	 * @param min
+	 * @param max
+	 */
+	public void removeRange(int min, int max) {
+
+	}
+
+	/**
+	 * 假设当前链表和参数list指定的链表均以元素依值递增有序排列（同一表中的元素值各不相同）
+	 * 现要求生成新链表C，其元素为当前链表和list中元素的交集，且表C中的元素有依值递增有序排列
+	 * 
+	 * @param list
+	 */
+	public LinkedList intersection(LinkedList list) {
+		return null;
+	}
+
+	public static void main(String[] args) {
+
+		LinkedList list = new LinkedList();
+		list.add("A");
+		list.add("B");
+		list.add("C");
+		list.add("D");
+		list.reverse();
+		Iterator it = list.iterator();
+		while (it.hasNext()) {
+			Object o = it.next();
+			System.out.println(o);
+		}
+
+	}
+}
\ No newline at end of file
diff --git a/group27/425044891/src/com/coding/basic/List.java b/group27/425044891/src/com/coding/basic/List.java
new file mode 100644
index 0000000000..c86b745572
--- /dev/null
+++ b/group27/425044891/src/com/coding/basic/List.java
@@ -0,0 +1,9 @@
+package com.coding.basic;
+
+public interface List {
+	public void add(Object o);
+	public void add(int index, Object o);
+	public Object get(int index);
+	public Object remove(int index);
+	public int size();
+}
\ No newline at end of file
diff --git a/group27/425044891/src/com/coding/basic/Queue.java b/group27/425044891/src/com/coding/basic/Queue.java
new file mode 100644
index 0000000000..fcec6ac57c
--- /dev/null
+++ b/group27/425044891/src/com/coding/basic/Queue.java
@@ -0,0 +1,37 @@
+package com.coding.basic;
+
+public class Queue {
+
+	private Object[] elementData = new Object[100];
+
+	int size = 0;
+
+	public void enQueue(Object o) {
+		if (size < 0 || size >= 100) {
+			throw new IndexOutOfBoundsException();
+		}
+		elementData[size++] = o;
+	}
+
+	public Object deQueue() {
+		if (size <= 0) {
+			throw new IndexOutOfBoundsException();
+		}
+		Object o = elementData[0];
+		int i = 0;
+		for (; i < size - 1; i++) {
+			elementData[i] = elementData[i + 1];
+		}
+		elementData[i] = null;
+		size--;
+		return o;
+	}
+
+	public boolean isEmpty() {
+		return elementData.length != 0;
+	}
+
+	public int size() {
+		return elementData.length;
+	}
+}
\ No newline at end of file
diff --git a/group27/425044891/src/com/coding/basic/Stack.java b/group27/425044891/src/com/coding/basic/Stack.java
new file mode 100644
index 0000000000..1217d25fbe
--- /dev/null
+++ b/group27/425044891/src/com/coding/basic/Stack.java
@@ -0,0 +1,29 @@
+package com.coding.basic;
+
+public class Stack {
+
+	private ArrayList elementData = new ArrayList();
+
+	public void push(Object o) {
+		int size = elementData.size();
+		elementData.add(size, o);
+	}
+
+	public Object pop() {
+		int size = elementData.size();
+		return elementData.remove(size - 1);
+	}
+
+	public Object peek() {
+		int size = elementData.size();
+		return elementData.get(size - 1);
+	}
+
+	public boolean isEmpty() {
+		return elementData.size() != 0;
+	}
+
+	public int size() {
+		return elementData.size();
+	}	
+}
\ No newline at end of file