diff --git a/C++/ClassDemo.cpp b/C++/ClassDemo.cpp
new file mode 100644
index 0000000..f437125
--- /dev/null
+++ b/C++/ClassDemo.cpp
@@ -0,0 +1,43 @@
+#include <iostream>
+using namespace std;
+
+class Animal
+{
+    protected:
+        char name[4] = "0";
+        int age = 0;
+        int height = 0;
+        double weight = 0;
+
+    public:
+        Animal(){}
+        ~Animal(){}
+        virtual void Walk() = 0;
+        virtual void Eat() = 0;
+        virtual void Sleep() = 0;
+};
+
+class Dog: public Animal
+{
+    public:
+        virtual void Walk(){};
+        virtual void Eat(){};
+        virtual void Sleep(){};
+};
+
+class Cat: public Animal
+{
+    public:
+        virtual void Walk(){}
+        virtual void Eat(){}
+        virtual void Sleep(){}
+};
+
+int main()
+{
+    Animal *animal;
+    Dog dog;
+    animal = &dog;
+    animal->Walk();
+	return 0;
+}
\ No newline at end of file
diff --git a/C++/InsertSort.cpp b/C++/InsertSort.cpp
new file mode 100644
index 0000000..550ed76
--- /dev/null
+++ b/C++/InsertSort.cpp
@@ -0,0 +1,25 @@
+#include <iostream>
+#include <vector>
+using namespace std;
+
+void InsertSort(vector<int> &num){
+	for(int i=1; i<num.size(); ++i){
+		int cur = num[i];
+		int position = i;
+		while(position>0 && num[position-1]>cur){
+			num[position] = num[position-1];
+			position--;
+		}
+		num[position] = cur;
+	}
+}
+
+int main()
+{
+	int a[9] = {54,26,93,17,77,31,44,55,20};
+	vector<int> num(a, a+9);
+	InsertSort(num);
+	for(int i=0;i<=num.size()-1;i++)
+    	cout<<num[i]<<" ";
+	return 0;
+}
\ No newline at end of file
diff --git a/SelectionSort.py b/SelectionSort.py
deleted file mode 100644
index bec257c..0000000
--- a/SelectionSort.py
+++ /dev/null
@@ -1,12 +0,0 @@
-# 选择排序, 纯粹练手 - -||
-def selectionSort(alist):
-    for i in range(len(alist)-1):
-        min = i
-        for j in range(i+1, len(alist)):
-            if alist[j] < alist[min]:
-                min = j
-        alist[i], alist[min] = alist[min], alist[i]
-    return alist
-
-alist = [54,26,93,17,77,31,44,55,20]
-print(selectionSort(alist))
\ No newline at end of file
diff --git a/BubbleSort.py b/Sort/BubbleSort.py
similarity index 58%
rename from BubbleSort.py
rename to Sort/BubbleSort.py
index 708cb4c..584ad14 100644
--- a/BubbleSort.py
+++ b/Sort/BubbleSort.py
@@ -22,4 +22,23 @@ def modiBubbleSort(alist):
         passnum -= 1
     return alist
 
-print(bubbleSort(alist))
\ No newline at end of file
+def bubbleSort2(array):
+    for i in range(len(array)):
+        for j in range(len(array)-1-i):
+            if array[j]>array[j+1]:
+                array[j],array[j+1] = array[j+1],array[j]
+    return array
+
+def modiBuddleSort2(array):
+    flag = True
+    i = 0
+    while i!=len(array) and flag:
+        flag = False
+        for j in range(len(array)-1-i):
+            if array[j]>array[j+1]:
+                array[j],array[j+1] = array[j+1],array[j]
+                flag = True
+        i+=1
+    return array
+
+print(modiBuddleSort2(alist))
\ No newline at end of file
diff --git a/InsertionSort.py b/Sort/InsertionSort.py
similarity index 68%
rename from InsertionSort.py
rename to Sort/InsertionSort.py
index 6e47d81..192f128 100644
--- a/InsertionSort.py
+++ b/Sort/InsertionSort.py
@@ -1,3 +1,5 @@
+# 时间复杂度 最好是O(n) 最差是O(n^2)
+
 def insertionSort(alist):
     for key, item in enumerate(alist):
         index = key
@@ -22,4 +24,15 @@ def insertionSort2(alist):
 
     return alist
 
+def insertSort3(array):
+    for i  in range(1,len(array)):
+        cur = array[i]
+        index = i
+
+        while index>0 and array[index-1]>cur:
+            array[index-1] = array[index]
+            index-=1
+        array[index] = cur
+    return array
+
 print(insertionSort2(alist))
diff --git a/QuickSort.py b/Sort/QuickSort.py
similarity index 72%
rename from QuickSort.py
rename to Sort/QuickSort.py
index 59b0972..d6d0824 100644
--- a/QuickSort.py
+++ b/Sort/QuickSort.py
@@ -30,6 +30,27 @@ def partition(alist, first, last):
     alist[rightmark], alist[first] = alist[first], alist[rightmark]
     return rightmark
 
+def quickSort2(array,start,end):
+    if start<=end:
+        return
+    k = array[start]
+    left = start
+    right = end
+
+    while left<right:
+        while left<right and array[right]>k:
+            right-=1
+        array[left],array[right] = array[right],array[left]
+
+        while left<right and array[left<=k]:
+            left+=1
+        array[left],array[right] = array[right],array[left]
+
+    quickSort2(array,start,left-1)
+    quickSort2(array,left,end)
+    return  array
+
+
 alist = [54,26,93,17,77,31,44,55,20]
 alist2 = [1]
 quickSort(alist2)
diff --git a/Sort/SelectionSort.py b/Sort/SelectionSort.py
new file mode 100644
index 0000000..b9919eb
--- /dev/null
+++ b/Sort/SelectionSort.py
@@ -0,0 +1,27 @@
+# 选择排序, 纯粹练手 - -||
+def selectionSort(alist):
+    for i in range(len(alist)-1):
+        min = i
+        for j in range(i+1, len(alist)):
+            if alist[j] < alist[min]:
+                min = j
+        alist[i], alist[min] = alist[min], alist[i]
+    return alist
+
+def selectionSort2(array):
+    for i in range(len(array)):
+        for j in range(i,len(array)):
+            if array[i]>array[j]:
+                array[i],array[j] = array[j],array[i]
+    return array
+
+def modiselectionSort(array):
+    for i in range(len(array)):
+        index = i
+        for j in range(i,len(array)):
+            if array[i]>array[j]:
+                index = j
+        array[i],array[index] = array[index],array[i]
+
+alist = [54,26,93,17,77,31,44,55,20]
+print(selectionSort(alist))
\ No newline at end of file
diff --git "a/Target Offer/\350\260\203\346\225\264\346\225\260\347\273\204\351\241\272\345\272\217\344\275\277\345\245\207\346\225\260\344\275\215\344\272\216\345\201\266\346\225\260\345\211\215\351\235\242.py" "b/Target Offer/10\350\260\203\346\225\264\346\225\260\347\273\204\351\241\272\345\272\217\344\275\277\345\245\207\346\225\260\344\275\215\344\272\216\345\201\266\346\225\260\345\211\215\351\235\242.py"
similarity index 100%
rename from "Target Offer/\350\260\203\346\225\264\346\225\260\347\273\204\351\241\272\345\272\217\344\275\277\345\245\207\346\225\260\344\275\215\344\272\216\345\201\266\346\225\260\345\211\215\351\235\242.py"
rename to "Target Offer/10\350\260\203\346\225\264\346\225\260\347\273\204\351\241\272\345\272\217\344\275\277\345\245\207\346\225\260\344\275\215\344\272\216\345\201\266\346\225\260\345\211\215\351\235\242.py"
diff --git "a/Target Offer/\351\223\276\350\241\250\344\270\255\345\200\222\346\225\260\347\254\254k\344\270\252\347\273\223\347\202\271.py" "b/Target Offer/11\351\223\276\350\241\250\344\270\255\345\200\222\346\225\260\347\254\254k\344\270\252\347\273\223\347\202\271.py"
similarity index 100%
rename from "Target Offer/\351\223\276\350\241\250\344\270\255\345\200\222\346\225\260\347\254\254k\344\270\252\347\273\223\347\202\271.py"
rename to "Target Offer/11\351\223\276\350\241\250\344\270\255\345\200\222\346\225\260\347\254\254k\344\270\252\347\273\223\347\202\271.py"
diff --git "a/Target Offer/\345\217\215\350\275\254\351\223\276\350\241\250.py" "b/Target Offer/12\345\217\215\350\275\254\351\223\276\350\241\250.py"
similarity index 75%
rename from "Target Offer/\345\217\215\350\275\254\351\223\276\350\241\250.py"
rename to "Target Offer/12\345\217\215\350\275\254\351\223\276\350\241\250.py"
index c8e2bb8..0af2a15 100644
--- "a/Target Offer/\345\217\215\350\275\254\351\223\276\350\241\250.py"	
+++ "b/Target Offer/12\345\217\215\350\275\254\351\223\276\350\241\250.py"	
@@ -9,6 +9,22 @@ def __init__(self, x):
         self.val = x
         self.next = None
 class Solution:
+
+    def ReverseList(self, pHead):
+        # write code here
+        if not pHead:
+            return
+        elif not pHead.next:
+            return pHead
+        pre = None
+        nextt = None
+        while pHead:
+            nextt = pHead.next
+            pHead.next = pre
+            pre = pHead
+            pHead = nextt
+        return pre
+
     # 返回ListNode
     def ReverseList(self, pHead):
         pReversedHead = None
diff --git "a/Target Offer/\345\220\210\345\271\266\344\270\244\344\270\252\346\216\222\345\272\217\347\232\204\351\223\276\350\241\250.py" "b/Target Offer/13\345\220\210\345\271\266\344\270\244\344\270\252\346\216\222\345\272\217\347\232\204\351\223\276\350\241\250.py"
similarity index 100%
rename from "Target Offer/\345\220\210\345\271\266\344\270\244\344\270\252\346\216\222\345\272\217\347\232\204\351\223\276\350\241\250.py"
rename to "Target Offer/13\345\220\210\345\271\266\344\270\244\344\270\252\346\216\222\345\272\217\347\232\204\351\223\276\350\241\250.py"
diff --git "a/Target Offer/\346\240\221\347\232\204\345\255\220\347\273\223\346\236\204.py" "b/Target Offer/14\346\240\221\347\232\204\345\255\220\347\273\223\346\236\204.py"
similarity index 100%
rename from "Target Offer/\346\240\221\347\232\204\345\255\220\347\273\223\346\236\204.py"
rename to "Target Offer/14\346\240\221\347\232\204\345\255\220\347\273\223\346\236\204.py"
diff --git "a/Target Offer/\344\272\214\345\217\211\346\240\221\347\232\204\351\225\234\345\203\217.py" "b/Target Offer/15\344\272\214\345\217\211\346\240\221\347\232\204\351\225\234\345\203\217.py"
similarity index 100%
rename from "Target Offer/\344\272\214\345\217\211\346\240\221\347\232\204\351\225\234\345\203\217.py"
rename to "Target Offer/15\344\272\214\345\217\211\346\240\221\347\232\204\351\225\234\345\203\217.py"
diff --git "a/Target Offer/\351\241\272\346\227\266\351\222\210\346\211\223\345\215\260\347\237\251\351\230\265.py" "b/Target Offer/16\351\241\272\346\227\266\351\222\210\346\211\223\345\215\260\347\237\251\351\230\265.py"
similarity index 100%
rename from "Target Offer/\351\241\272\346\227\266\351\222\210\346\211\223\345\215\260\347\237\251\351\230\265.py"
rename to "Target Offer/16\351\241\272\346\227\266\351\222\210\346\211\223\345\215\260\347\237\251\351\230\265.py"
diff --git "a/Target Offer/\345\214\205\345\220\253min\345\207\275\346\225\260\347\232\204\346\240\210.py" "b/Target Offer/17\345\214\205\345\220\253min\345\207\275\346\225\260\347\232\204\346\240\210.py"
similarity index 100%
rename from "Target Offer/\345\214\205\345\220\253min\345\207\275\346\225\260\347\232\204\346\240\210.py"
rename to "Target Offer/17\345\214\205\345\220\253min\345\207\275\346\225\260\347\232\204\346\240\210.py"
diff --git "a/Target Offer/\346\240\210\347\232\204\345\216\213\345\205\245\345\274\271\345\207\272\345\272\217\345\210\227.py" "b/Target Offer/18\346\240\210\347\232\204\345\216\213\345\205\245\345\274\271\345\207\272\345\272\217\345\210\227.py"
similarity index 76%
rename from "Target Offer/\346\240\210\347\232\204\345\216\213\345\205\245\345\274\271\345\207\272\345\272\217\345\210\227.py"
rename to "Target Offer/18\346\240\210\347\232\204\345\216\213\345\205\245\345\274\271\345\207\272\345\272\217\345\210\227.py"
index 1350125..9d9da61 100644
--- "a/Target Offer/\346\240\210\347\232\204\345\216\213\345\205\245\345\274\271\345\207\272\345\272\217\345\210\227.py"	
+++ "b/Target Offer/18\346\240\210\347\232\204\345\216\213\345\205\245\345\274\271\345\207\272\345\272\217\345\210\227.py"	
@@ -44,8 +44,23 @@ def IsPopOrder2(self, pushV, popV):
         else:
             return True
 
+    def IsPopOrder3(self, pushV, popV):
+        # write code here
+        if pushV == [] or popV == []:
+            return False
+        stack = []
+        for i in pushV:
+            stack.append(i)
+            while len(stack) and stack[-1] == popV[0]:
+                stack.pop()
+                popV.pop(0)
+            if len(stack):
+                return False
+            else:
+                return True
+
 pushV = [1, 2, 3, 4, 5]
 popV = [4, 5, 3, 2, 1]
 popVF = [4, 5, 2, 1, 3]
 S = Solution()
-print(S.IsPopOrder2(pushV, popVF))
+print(S.IsPopOrder3(pushV, popV))
diff --git "a/Target Offer/\344\273\216\344\270\212\345\276\200\344\270\213\346\211\223\345\215\260\344\272\214\345\217\211\346\240\221.py" "b/Target Offer/19\344\273\216\344\270\212\345\276\200\344\270\213\346\211\223\345\215\260\344\272\214\345\217\211\346\240\221.py"
similarity index 100%
rename from "Target Offer/\344\273\216\344\270\212\345\276\200\344\270\213\346\211\223\345\215\260\344\272\214\345\217\211\346\240\221.py"
rename to "Target Offer/19\344\273\216\344\270\212\345\276\200\344\270\213\346\211\223\345\215\260\344\272\214\345\217\211\346\240\221.py"
diff --git "a/Target Offer/\344\272\214\347\273\264\346\225\260\347\273\204\346\237\245\346\211\276.py" "b/Target Offer/1\344\272\214\347\273\264\346\225\260\347\273\204\346\237\245\346\211\276.py"
similarity index 90%
rename from "Target Offer/\344\272\214\347\273\264\346\225\260\347\273\204\346\237\245\346\211\276.py"
rename to "Target Offer/1\344\272\214\347\273\264\346\225\260\347\273\204\346\237\245\346\211\276.py"
index 81239fd..ff7b14e 100644
--- "a/Target Offer/\344\272\214\347\273\264\346\225\260\347\273\204\346\237\245\346\211\276.py"	
+++ "b/Target Offer/1\344\272\214\347\273\264\346\225\260\347\273\204\346\237\245\346\211\276.py"	
@@ -18,6 +18,21 @@
 
 class Solution:
     # array 二维列表
+
+    def easyFind(self,array,target):
+        row = len(array)
+        col = len(array[0])
+        i=row-1
+        j=0
+        while j<col and i>=0:
+            if target<array[i][j]:
+                i-=1
+            elif target>array[i][j]:
+                j-=1
+            else:
+                return True
+        return False
+
     def Find(self, array, target):
         # 判断数组是否为空
         if array == []:
diff --git "a/Target Offer/\344\272\214\345\217\211\346\220\234\347\264\242\346\240\221\347\232\204\345\220\216\347\273\255\351\201\215\345\216\206\345\272\217\345\210\227.py" "b/Target Offer/20\344\272\214\345\217\211\346\220\234\347\264\242\346\240\221\347\232\204\345\220\216\347\273\255\351\201\215\345\216\206\345\272\217\345\210\227.py"
similarity index 99%
rename from "Target Offer/\344\272\214\345\217\211\346\220\234\347\264\242\346\240\221\347\232\204\345\220\216\347\273\255\351\201\215\345\216\206\345\272\217\345\210\227.py"
rename to "Target Offer/20\344\272\214\345\217\211\346\220\234\347\264\242\346\240\221\347\232\204\345\220\216\347\273\255\351\201\215\345\216\206\345\272\217\345\210\227.py"
index b1533eb..8798c78 100644
--- "a/Target Offer/\344\272\214\345\217\211\346\220\234\347\264\242\346\240\221\347\232\204\345\220\216\347\273\255\351\201\215\345\216\206\345\272\217\345\210\227.py"	
+++ "b/Target Offer/20\344\272\214\345\217\211\346\220\234\347\264\242\346\240\221\347\232\204\345\220\216\347\273\255\351\201\215\345\216\206\345\272\217\345\210\227.py"	
@@ -13,8 +13,10 @@ def VerifySquenceOfBST(self, sequence):
 
         root = sequence[-1]
         length = len(sequence)
+
         if min(sequence) > root or max(sequence) < root:
             return True
+
         index = 0
         # 二叉搜索树的左子树结点小于根节点
         '''
diff --git "a/Target Offer/\344\272\214\345\217\211\346\240\221\344\270\255\345\222\214\344\270\272\346\237\220\344\270\200\345\200\274\347\232\204\350\267\257\345\276\204.py" "b/Target Offer/21\344\272\214\345\217\211\346\240\221\344\270\255\345\222\214\344\270\272\346\237\220\344\270\200\345\200\274\347\232\204\350\267\257\345\276\204.py"
similarity index 100%
rename from "Target Offer/\344\272\214\345\217\211\346\240\221\344\270\255\345\222\214\344\270\272\346\237\220\344\270\200\345\200\274\347\232\204\350\267\257\345\276\204.py"
rename to "Target Offer/21\344\272\214\345\217\211\346\240\221\344\270\255\345\222\214\344\270\272\346\237\220\344\270\200\345\200\274\347\232\204\350\267\257\345\276\204.py"
diff --git "a/Target Offer/\345\244\215\346\235\202\351\223\276\350\241\250\347\232\204\345\244\215\345\210\266.py" "b/Target Offer/22\345\244\215\346\235\202\351\223\276\350\241\250\347\232\204\345\244\215\345\210\266.py"
similarity index 100%
rename from "Target Offer/\345\244\215\346\235\202\351\223\276\350\241\250\347\232\204\345\244\215\345\210\266.py"
rename to "Target Offer/22\345\244\215\346\235\202\351\223\276\350\241\250\347\232\204\345\244\215\345\210\266.py"
diff --git "a/Target Offer/\344\272\214\345\217\211\346\220\234\347\264\242\346\240\221\344\270\216\345\217\214\345\220\221\351\223\276\350\241\250.py" "b/Target Offer/23\344\272\214\345\217\211\346\220\234\347\264\242\346\240\221\344\270\216\345\217\214\345\220\221\351\223\276\350\241\250.py"
similarity index 100%
rename from "Target Offer/\344\272\214\345\217\211\346\220\234\347\264\242\346\240\221\344\270\216\345\217\214\345\220\221\351\223\276\350\241\250.py"
rename to "Target Offer/23\344\272\214\345\217\211\346\220\234\347\264\242\346\240\221\344\270\216\345\217\214\345\220\221\351\223\276\350\241\250.py"
diff --git "a/Target Offer/\345\255\227\347\254\246\344\270\262\347\232\204\346\216\222\345\210\227\345\222\214\347\273\204\345\220\210.py" "b/Target Offer/24\345\255\227\347\254\246\344\270\262\347\232\204\346\216\222\345\210\227\345\222\214\347\273\204\345\220\210.py"
similarity index 97%
rename from "Target Offer/\345\255\227\347\254\246\344\270\262\347\232\204\346\216\222\345\210\227\345\222\214\347\273\204\345\220\210.py"
rename to "Target Offer/24\345\255\227\347\254\246\344\270\262\347\232\204\346\216\222\345\210\227\345\222\214\347\273\204\345\220\210.py"
index 7b16f6d..f36535f 100644
--- "a/Target Offer/\345\255\227\347\254\246\344\270\262\347\232\204\346\216\222\345\210\227\345\222\214\347\273\204\345\220\210.py"	
+++ "b/Target Offer/24\345\255\227\347\254\246\344\270\262\347\232\204\346\216\222\345\210\227\345\222\214\347\273\204\345\220\210.py"	
@@ -47,6 +47,7 @@ def group(self, ss):
         return pStr
 
 ss = 'acb'
+sss = 'aabc'
 S = Solution()
 # print(S.Permutation(ss))
-print(S.group(ss))
\ No newline at end of file
+print(S.Permutation(sss))
\ No newline at end of file
diff --git "a/Target Offer/\346\225\260\347\273\204\344\270\255\345\207\272\347\216\260\346\254\241\346\225\260\350\266\205\350\277\207\344\270\200\345\215\212\347\232\204\346\225\260\345\255\227.py" "b/Target Offer/25\346\225\260\347\273\204\344\270\255\345\207\272\347\216\260\346\254\241\346\225\260\350\266\205\350\277\207\344\270\200\345\215\212\347\232\204\346\225\260\345\255\227.py"
similarity index 100%
rename from "Target Offer/\346\225\260\347\273\204\344\270\255\345\207\272\347\216\260\346\254\241\346\225\260\350\266\205\350\277\207\344\270\200\345\215\212\347\232\204\346\225\260\345\255\227.py"
rename to "Target Offer/25\346\225\260\347\273\204\344\270\255\345\207\272\347\216\260\346\254\241\346\225\260\350\266\205\350\277\207\344\270\200\345\215\212\347\232\204\346\225\260\345\255\227.py"
diff --git "a/Target Offer/\346\233\277\346\215\242\347\251\272\346\240\274.py" "b/Target Offer/2\346\233\277\346\215\242\347\251\272\346\240\274.py"
similarity index 79%
rename from "Target Offer/\346\233\277\346\215\242\347\251\272\346\240\274.py"
rename to "Target Offer/2\346\233\277\346\215\242\347\251\272\346\240\274.py"
index bd15a41..13b560d 100644
--- "a/Target Offer/\346\233\277\346\215\242\347\251\272\346\240\274.py"	
+++ "b/Target Offer/2\346\233\277\346\215\242\347\251\272\346\240\274.py"	
@@ -6,20 +6,27 @@
 # -*- coding:utf-8 -*-
 class Solution:
     # s 源字符串
-    
+
+    def replaceSpaceByList(self, s):
+        s = list(s)
+        for i in range(len(s)):
+            if s[i] == ' ':
+                s[i] = '%20'
+        return ''.join(s)
+
     # 使用append一次遍历即可替换
     # 由于list的append是O(1)的时间复杂度，除了扩容所导致的时间损耗，该算法复杂度为O(n)
     def replaceSpaceByAppend(self, s):
-        string = list(string)
-	    stringReplace = []
-	    for item in string:
-		    if item == ' ':
-			    stringReplace.append('%')
-			    stringReplace.append('2')
-			    stringReplace.append('0')
-		    else:
-			    stringReplace.append(item)
-	    return "".join(stringReplace)
+        string = list(s)
+        stringReplace = []
+        for item in string:
+            if item == ' ':
+                stringReplace.append('%')
+                stringReplace.append('2')
+                stringReplace.append('0')
+            else:
+                stringReplace.append(item)
+        return "".join(stringReplace)
 
     # 创建新的字符串进行替换
     def replaceSpace1(self, s):
@@ -70,3 +77,4 @@ def replaceSpace3(self, s):
 print(test.replaceSpace1(s))
 print(test.replaceSpace2(s))
 print(test.replaceSpace3(s))
+print(test.replaceSpaceByList(s))
diff --git "a/Target Offer/\345\217\215\345\220\221\346\211\223\345\215\260\351\223\276\350\241\250.py" "b/Target Offer/3\345\217\215\345\220\221\346\211\223\345\215\260\351\223\276\350\241\250.py"
similarity index 93%
rename from "Target Offer/\345\217\215\345\220\221\346\211\223\345\215\260\351\223\276\350\241\250.py"
rename to "Target Offer/3\345\217\215\345\220\221\346\211\223\345\215\260\351\223\276\350\241\250.py"
index ad0a21d..35d3c59 100644
--- "a/Target Offer/\345\217\215\345\220\221\346\211\223\345\215\260\351\223\276\350\241\250.py"	
+++ "b/Target Offer/3\345\217\215\345\220\221\346\211\223\345\215\260\351\223\276\350\241\250.py"	
@@ -8,7 +8,7 @@ def __init__(self, x=None):
 
 class Solution:
     def printListFromTailToHead(self, listNode):
-        if listNode.val == None:
+        if listNode==None or listNode.val == None:
             return
         l = []
         head = listNode
diff --git "a/Target Offer/\351\207\215\345\273\272\344\272\214\345\217\211\346\240\221.py" "b/Target Offer/4\351\207\215\345\273\272\344\272\214\345\217\211\346\240\221.py"
similarity index 80%
rename from "Target Offer/\351\207\215\345\273\272\344\272\214\345\217\211\346\240\221.py"
rename to "Target Offer/4\351\207\215\345\273\272\344\272\214\345\217\211\346\240\221.py"
index dc7f872..8296334 100644
--- "a/Target Offer/\351\207\215\345\273\272\344\272\214\345\217\211\346\240\221.py"	
+++ "b/Target Offer/4\351\207\215\345\273\272\344\272\214\345\217\211\346\240\221.py"	
@@ -12,6 +12,18 @@ def __init__(self, x):
         self.right = None
 class Solution:
     # 返回构造的TreeNode根节点
+    def reConstructBinaryTree2(self, pre, tin):
+        if len(pre)==0:
+            return None
+        if len(pre)==1:
+            return pre[0]
+        # write code here
+        root = TreeNode(pre[0])
+        i = tin.index(pre[0])
+        root.left = self.reConstructBinaryTree(pre[1:i+1],tin[:i])
+        root.right = self.reConstructBinaryTree(pre[i+1:],tin[i+1:])
+        return root
+
     def reConstructBinaryTree(self, pre, tin):
         # write code here
         if not pre and not tin:
@@ -28,6 +40,7 @@ def reConstructBinaryTree(self, pre, tin):
 tin = [5, 3, 6, 2, 4, 1]
 test = Solution()
 newTree = test.reConstructBinaryTree(pre, tin)
+newTree2 = test.reConstructBinaryTree2(pre, tin)
 # 按层序遍历输出树中某一层的值
 def PrintNodeAtLevel(treeNode, level):
     if not treeNode or level < 0:
diff --git "a/Target Offer/\347\224\250\344\270\244\344\270\252\346\240\210\345\256\236\347\216\260\351\230\237\345\210\227.py" "b/Target Offer/5\347\224\250\344\270\244\344\270\252\346\240\210\345\256\236\347\216\260\351\230\237\345\210\227.py"
similarity index 100%
rename from "Target Offer/\347\224\250\344\270\244\344\270\252\346\240\210\345\256\236\347\216\260\351\230\237\345\210\227.py"
rename to "Target Offer/5\347\224\250\344\270\244\344\270\252\346\240\210\345\256\236\347\216\260\351\230\237\345\210\227.py"
diff --git "a/Target Offer/\346\227\213\350\275\254\346\225\260\347\273\204\347\232\204\346\234\200\345\260\217\346\225\260\345\255\227.py" "b/Target Offer/6\346\227\213\350\275\254\346\225\260\347\273\204\347\232\204\346\234\200\345\260\217\346\225\260\345\255\227.py"
similarity index 98%
rename from "Target Offer/\346\227\213\350\275\254\346\225\260\347\273\204\347\232\204\346\234\200\345\260\217\346\225\260\345\255\227.py"
rename to "Target Offer/6\346\227\213\350\275\254\346\225\260\347\273\204\347\232\204\346\234\200\345\260\217\346\225\260\345\255\227.py"
index a33dbe0..78a26d3 100644
--- "a/Target Offer/\346\227\213\350\275\254\346\225\260\347\273\204\347\232\204\346\234\200\345\260\217\346\225\260\345\255\227.py"	
+++ "b/Target Offer/6\346\227\213\350\275\254\346\225\260\347\273\204\347\232\204\346\234\200\345\260\217\346\225\260\345\255\227.py"	
@@ -39,7 +39,7 @@ def minNumberInRotateArray2(self, rotateArray):
             if rear - front == 1:
                 midIndex = rear
                 break
-            midIndex = (front + rear) // 2
+            midIndex = (front + rear) >> 1
             if rotateArray[front] == rotateArray[rear] and rotateArray[front] == rotateArray[midIndex]:
                 return self.MinInOrder(rotateArray, front, rear)
 
diff --git "a/Target Offer/\346\226\220\346\263\242\351\202\243\345\245\221\346\225\260\345\210\227.py" "b/Target Offer/7\346\226\220\346\263\242\351\202\243\345\245\221\346\225\260\345\210\227.py"
similarity index 62%
rename from "Target Offer/\346\226\220\346\263\242\351\202\243\345\245\221\346\225\260\345\210\227.py"
rename to "Target Offer/7\346\226\220\346\263\242\351\202\243\345\245\221\346\225\260\345\210\227.py"
index 1641cc1..afd6524 100644
--- "a/Target Offer/\346\226\220\346\263\242\351\202\243\345\245\221\346\225\260\345\210\227.py"	
+++ "b/Target Offer/7\346\226\220\346\263\242\351\202\243\345\245\221\346\225\260\345\210\227.py"	
@@ -27,6 +27,22 @@ def jumpFloorII(self, number):
                 ans = ans * 2
         return ans
 
+# 矩形覆盖
+    # 第一次摆放一块1*2的小矩阵，则摆放方法总共为f(target-2)
+    # 因为，摆放了一块1*2的小矩阵（用√√表示），对应下方的1*2（用××表示）摆放方法就确定了，所以为f(targte-2)
+
+    def rectCover(self, number):
+        if number == 0:
+            return 0
+        if number == 1:
+            return 1
+        temp = [1, 2]
+
+        if number >= 3:
+            for i in range(3, number + 1):
+                temp[(i + 1) % 2] = temp[0] + temp[1]
+        return temp[(number + 1) % 2]
+
 test = Solution()
 print(test.Fibonacci(100))
 print(test.jumpFloor(3))
diff --git "a/Target Offer/\344\272\214\350\277\233\345\210\266\344\270\2551\347\232\204\344\270\252\346\225\260.py" "b/Target Offer/8\344\272\214\350\277\233\345\210\266\344\270\2551\347\232\204\344\270\252\346\225\260.py"
similarity index 100%
rename from "Target Offer/\344\272\214\350\277\233\345\210\266\344\270\2551\347\232\204\344\270\252\346\225\260.py"
rename to "Target Offer/8\344\272\214\350\277\233\345\210\266\344\270\2551\347\232\204\344\270\252\346\225\260.py"
diff --git "a/Target Offer/\346\225\260\345\200\274\347\232\204\346\225\264\346\225\260\346\254\241\346\226\271.py" "b/Target Offer/9\346\225\260\345\200\274\347\232\204\346\225\264\346\225\260\346\254\241\346\226\271.py"
similarity index 100%
rename from "Target Offer/\346\225\260\345\200\274\347\232\204\346\225\264\346\225\260\346\254\241\346\226\271.py"
rename to "Target Offer/9\346\225\260\345\200\274\347\232\204\346\225\264\346\225\260\346\254\241\346\226\271.py"