diff --git a/README.md b/README.md
index 9a15e491..6dda5d7f 100644
--- a/README.md
+++ b/README.md
@@ -1,19 +1,21 @@
 # leetcode
-LeetCode 最强题解
+> 笔者介绍
+> ACM亚洲区域赛铜牌获得者，哈工大计算机硕士毕业后，先后在腾讯和百度工作多年，对算法和后端技术有一定的见解，利用工作之余重新刷leetcode
+> 欢迎关注微信公众号：「代码随想录」，这里将持续分享自己对互联网以及技术的想法与思考
+
+LeetCode 最强题解（持续更新中）:
+
 |题目 | 类型 | 解题方法 |
 |---|---| ---|
 |[0000.两数之和](https://github.com/youngyangyang04/leetcode/blob/master/problems/0000.%E4%B8%A4%E6%95%B0%E4%B9%8B%E5%92%8C.md) | 数组|**暴力** **哈希**| 
 |[0021.合并两个有序链表](https://github.com/youngyangyang04/leetcode/blob/master/problems/0021.合并两个有序链表.md)  |链表 |**模拟** |
 |[0026.删除排序数组中的重复项](https://github.com/youngyangyang04/leetcode/blob/master/problems/0026.删除排序数组中的重复项.md)  |数组 |**暴力** **快慢指针** |
-|[0027.移除元素](https://github.com/youngyangyang04/leetcode/blob/master/problems/0027.移除元素.md)  |数组 | **暴力**、**快慢指针**|
-|[0035.搜索插入位置](https://github.com/youngyangyang04/leetcode/blob/master/problems/0035.搜索插入位置.md) |数组 | **暴力**、**二分**|
+|[0027.移除元素](https://github.com/youngyangyang04/leetcode/blob/master/problems/0027.移除元素.md)  |数组 | **暴力** **快慢指针**|
+|[0035.搜索插入位置](https://github.com/youngyangyang04/leetcode/blob/master/problems/0035.搜索插入位置.md) |数组 | **暴力** **二分**|
 |[0053.最大子序和](https://github.com/youngyangyang04/leetcode/blob/master/problems/0053.最大子序和.md) |数组 |**暴力** **贪心** 动态规划 分治|
 |[0059.螺旋矩阵II](https://github.com/youngyangyang04/leetcode/blob/master/problems/0059.螺旋矩阵II.md) |数组 |**模拟**|
 |[0209.长度最小的子数组](https://github.com/youngyangyang04/leetcode/blob/master/problems/0209.长度最小的子数组.md) |数组 | **暴力** **滑动窗口**|
 |[0237.删除链表中的节点](https://github.com/youngyangyang04/leetcode/blob/master/problems/0237.删除链表中的节点.md) |链表 | **暴力**|
 |[0383.赎金信](https://github.com/youngyangyang04/leetcode/blob/master/problems/0383.赎金信.md) |数组 |**暴力** **字典计数**|
 
-> 笔者介绍
-> ACM亚洲区域赛铜牌获得者，哈工大计算机硕士毕业后，先后在腾讯和百度工作多年，对算法和后端技术有一定的见解
-> 欢迎关注公众号：「代码随想录」这里将持续分享自己对互联网以及技术的想法与思考
 
diff --git a/algorithm_interview_course/chapter_two/section_2.cpp b/algorithm_interview_course/chapter_two/section_2.cpp
deleted file mode 100644
index 39a74475..00000000
--- a/algorithm_interview_course/chapter_two/section_2.cpp
+++ /dev/null
@@ -1,65 +0,0 @@
-/* ************************************************************************
-> File Name:     algorithm_2.cpp
-> Author:        sunxiuyang
-> Mail:          sunxiuyang04@gmail.com 
-> Created Time:  Thu Jan 30 16:09:35 2020
-> Description:   
- ************************************************************************/
-
-#include <iostream>
-#include <chrono>
-#include <thread>
-using namespace std;
-using namespace chrono;
-
-// O(n)
-void function1(long long n) {
-    long long k = 0;
-    for (long long i = 0; i < n; i++) {
-        k++;
-    }
-}
-
-// O(n^2)
-void function2(long long n) {
-    long long k = 0;
-    for (long long i = 0; i < n; i++) {
-        for (long j = 0; j < n; j++) {
-            k++;
-        }
-    }
-
-}
-
-// O(nlogn)
-void function3(long long n) {
-    long long k = 0;
-    for (long long i = 0; i < n; i++) {
-        for (long long j = 1; j < n; j = j*2) { // 注意这里j=1
-            k++;
-        }
-    }
-}
-
-
-void time_test() {
-    long long n; // 数据规模
-    while (cin>>n) {
-        milliseconds start_time = duration_cast<milliseconds >(
-            system_clock::now().time_since_epoch()
-        );
-
-        function3(n);
-
-        milliseconds end_time = duration_cast<milliseconds >(
-            system_clock::now().time_since_epoch()
-        );
-        cout << milliseconds(end_time).count() - milliseconds(start_time).count() 
-            <<" ms"<< endl;
-    }
-}
-
-int main() {
-    time_test();
-}
-
diff --git a/algorithm_interview_course/chapter_two/section_3.cpp b/algorithm_interview_course/chapter_two/section_3.cpp
deleted file mode 100644
index 77e9f9fc..00000000
--- a/algorithm_interview_course/chapter_two/section_3.cpp
+++ /dev/null
@@ -1,55 +0,0 @@
-/* ************************************************************************
-> File Name:     section_3.cpp
-> Author:        sunxiuyang
-> Mail:          sunxiuyang04@gmail.com 
-> Created Time:  Sat Feb  8 22:00:32 2020
-> Description:   
- ************************************************************************/
-
-#include<iostream>
-using namespace std;
-
-int function1(int x, int n) {
-    int result = 1;  // 注意 任何数的0次方等于1 
-    for (int i = 0; i < n; i++) {
-        result = result * x;
-    }
-    return result;
-}
-
-int function2(int x, int n) {
-    if (n == 0) {
-        return 1; // return 1 同样是因为0次方是等于1的
-    }
-    return function2(x, n - 1) * x;
-}
-
-int function3(int x, int n) {
-    if (n == 0) {
-        return 1;
-    }
-    // if (n == 1) { // 这里如果不作处理就会陷入死循环
-    //     return x;
-    // }
-    if (n % 2 == 1) {
-        return function3(x, n/2) * function3(x, n/2) * x;
-    } 
-    return function3(x, n/2) * function3(x, n/2);
-}
-
-int function4(int x, int n) {
-    if (n == 0) {
-        return 1;
-    }
-    int t = function4(x, n/2);
-    if (n % 2 == 1) {
-        return t*t*x;
-    } 
-    return t*t;
-}
-int main() {
-    int x, n;
-    while (cin >> x >> n) {
-        cout << function3(x, n) << endl;
-    }
-}
diff --git a/algorithm_interview_course/chapter_two/section_4.cpp b/algorithm_interview_course/chapter_two/section_4.cpp
deleted file mode 100644
index 84ddd192..00000000
--- a/algorithm_interview_course/chapter_two/section_4.cpp
+++ /dev/null
@@ -1,25 +0,0 @@
-/* ************************************************************************
-> File Name:     section_4.cpp
-> Author:        sunxiuyang
-> Mail:          sunxiuyang04@gmail.com 
-> Created Time:  Tue Feb 18 23:34:08 2020
-> Description:   
- ************************************************************************/
-
-#include<iostream> 
-using namespace std;
-
-struct node{
-   int num;
-   char cha;
-}st;
-
-int main() {
-    int a[100];
-    char b[100];
-    cout << sizeof(int) << endl;
-    cout << sizeof(char) << endl;
-    cout << sizeof(a) << endl;
-    cout << sizeof(b) << endl;
-    cout << sizeof(st) << endl;
-}
diff --git a/algorithm_interview_course/chapter_two/section_5.cpp b/algorithm_interview_course/chapter_two/section_5.cpp
deleted file mode 100644
index 1c6415b6..00000000
--- a/algorithm_interview_course/chapter_two/section_5.cpp
+++ /dev/null
@@ -1,104 +0,0 @@
-/* ************************************************************************
-> File Name:     section_5.cpp
-> Author:        sunxiuyang
-> Mail:          sunxiuyang04@gmail.com 
-> Created Time:  Mon Feb 24 18:44:56 2020
-> Description:   
- ************************************************************************/
-
-#include <iostream>
-#include <chrono>
-#include <thread>
-using namespace std;
-using namespace chrono;
-
-int fibonacci_1(int n) {
-    if (n <= 0) {
-        return 0;
-    }
-    if (n == 1 || n == 2) {
-        return 1;
-    }
-    int first = 1, second = 1; 
-    int sum = first + second; 
-    for (int i = 2; i < n; i++) {
-        sum = first + second;
-        first = second;
-        second = sum;
-    }
-    return sum;
-}
-
-
-int fibonacci_2(int i) {
-       if(i <= 0) return 0;
-       if(i == 1) return 1;
-       return fibonacci_2(i - 1) + fibonacci_2(i - 2);
-}
-
-int fibonacci_3(int first, int second, int n) {
-    if (n <= 0) {
-        return 0;
-    }
-    if (n < 3) {
-        return 1;
-    }
-    else if (n == 3) {
-        return first + second;
-    }
-    else {
-        return fibonacci_3(second, first + second, n - 1);
-    }
-}
-
-
-void test_fibonacci() {
-    int n;
-    while(cin >> n) {
-        cout << fibonacci_1(n) << endl;
-        cout << fibonacci_2(n) << endl;
-        cout << fibonacci_3(1, 1, n) << endl;
-    } 
-}
-
-int binary_search(int arr[], int l, int r, int n) {
-    if (r >= l) {
-        int mid = l + (r - l) / 2;
-        if (arr[mid] == n)
-            return mid;
-        if (arr[mid] > n)
-            return binary_search(arr, l, mid - 1, n);
-        return binary_search(arr, mid + 1, r, n);
-    }
-    return -1;
-}
-int arr[] = {2, 3, 4, 5, 8, 10, 15, 17, 20};
-int binary_search(int l, int r, int n) {
-    if (r >= l) {
-        int mid = l + (r - l) / 2;
-        if (arr[mid] == n)
-            return mid;
-        if (arr[mid] > n)
-            return binary_search(l, mid - 1, n);
-        return binary_search(mid + 1, r, n);
-    }
-    return -1;
-}
-
-void test_binary_search(void) {
-    int arr[] = {2, 3, 4, 5, 8, 10, 15, 17, 20};
-    int x = 17;
-    int n = sizeof(arr) / sizeof(arr[0]);
-    // int result = binary_search(arr, 0, n - 1, x);
-    int result = binary_search(0, n - 1, x);
-    (result == -1) ? cout << "Element is not present in array"
-                   : cout << "Element is present at index " << result;
-}
-
-int main()
-{
-    // test_binary_search();
-    // test_fibonacci();
-    return 0;
-}
-
diff --git a/algorithm_interview_course/chapter_two/section_6.cpp b/algorithm_interview_course/chapter_two/section_6.cpp
deleted file mode 100644
index a63ae21d..00000000
--- a/algorithm_interview_course/chapter_two/section_6.cpp
+++ /dev/null
@@ -1,33 +0,0 @@
-
-#include <iostream>
-#include <chrono>
-#include <thread>
-using namespace std;
-using namespace chrono;
-int fibonacci_2(int i) {
-       if(i <= 0) return 0;
-       if(i == 1) return 1;
-       return fibonacci_2(i - 1) + fibonacci_2(i - 2);
-}
-void time_consumption() {
-    int n;
-    while (cin >> n) {
-        milliseconds start_time = duration_cast<milliseconds >(
-            system_clock::now().time_since_epoch()
-        );
-
-        fibonacci_2(n);
-
-        milliseconds end_time = duration_cast<milliseconds >(
-            system_clock::now().time_since_epoch()
-        );
-        cout << milliseconds(end_time).count() - milliseconds(start_time).count() 
-            <<" ms"<< endl;
-    }
-}
-int main()
-{
-    time_consumption();
-    return 0;
-}
-