docs: 更新 README

mluckydream · Jun 16, 2020 · e4394dd · e4394dd
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diff --git a/README.md b/README.md
@@ -31,6 +31,23 @@
 
 ![](https://tva1.sinaimg.cn/large/007S8ZIlly1gdvenxvjlsj30z90dtdhw.jpg)
 
+## 非科学人士看过来
+
+如果是国内的非科学用户，可以使用 https://lucifer.ren/leetcode ，整站做了静态化，速度贼快！但是阅读体验可能一般，大家也可以访问[力扣加加](http://leetcode-solution.cn/)（暂时没有静态化）获得更好的阅读体验。
+
+## 怎么刷 LeetCode？
+
+- [我是如何刷 LeetCode 的](https://www.zhihu.com/question/280279208/answer/824585814)
+- [算法小白如何高效、快速刷 leetcode？](https://www.zhihu.com/question/321738058/answer/1279464192)
+
+## 刷题插件(开发中)
+
+- [刷题效率低？或许你就差这么一个插件](https://lucifer.ren/blog/2020/06/06/algo-chrome-extension/)
+
+## 91 天学算法
+
+- [91 天，遇见不一样的自己](https://lucifer.ren/blog/2020/05/23/91-algo/)
+
 ## 介绍
 
 leetcode 题解，记录自己的 leetcode 解题之路。
@@ -311,12 +328,13 @@ leetcode 题解，记录自己的 leetcode 解题之路。
 - [《贪婪策略》专题](./thinkings/greedy.md)
 - [《深度优先遍历》专题](./thinkings/DFS.md)
 - [滑动窗口（思路 + 模板）](./thinkings/slide-window.md)
-- [位运算](./thinkings/bit.md) 🆕
+- [位运算](./thinkings/bit.md)
 - [设计题](./thinkings/design.md) 🆕
-- [小岛问题](./thinkings/island.md) 🆕
+- [小岛问题](./thinkings/island.md)
 - [最大公约数](./thinkings/GCD.md) 🆕
 - [并查集](./thinkings/union-find.md) 🆕
 - [前缀和](./thinkings/prefix.md) 🆕
+- [字典序列删除](https://lucifer.ren/blog/2020/06/13/%E5%88%A0%E9%99%A4%E9%97%AE%E9%A2%98/)🆕
 
 ### anki 卡片
 
@@ -368,6 +386,8 @@ anki - 文件 - 导入 - 下拉格式选择“打包的 anki 集合”，然后
 
 - 单调栈
 
+- BFS & DFS
+
 ## 关注我
 
 点关注，不迷路。如果再给 ➕ 个星标就更棒啦！

diff --git a/problems/887.super-egg-drop.md b/problems/887.super-egg-drop.md
@@ -1,29 +1,29 @@
-
 ## 题目地址
+
 https://leetcode.com/problems/super-egg-drop/description/
 
 ## 题目描述
 
 ```
-You are given K eggs, and you have access to a building with N floors from 1 to N. 
+You are given K eggs, and you have access to a building with N floors from 1 to N.
 
 Each egg is identical in function, and if an egg breaks, you cannot drop it again.
 
 You know that there exists a floor F with 0 <= F <= N such that any egg dropped at a floor higher than F will break, and any egg dropped at or below floor F will not break.
 
-Each move, you may take an egg (if you have an unbroken one) and drop it from any floor X (with 1 <= X <= N). 
+Each move, you may take an egg (if you have an unbroken one) and drop it from any floor X (with 1 <= X <= N).
 
 Your goal is to know with certainty what the value of F is.
 
 What is the minimum number of moves that you need to know with certainty what F is, regardless of the initial value of F?
 
- 
+
 
 Example 1:
 
 Input: K = 1, N = 2
 Output: 2
-Explanation: 
+Explanation:
 Drop the egg from floor 1.  If it breaks, we know with certainty that F = 0.
 Otherwise, drop the egg from floor 2.  If it breaks, we know with certainty that F = 1.
 If it didn't break, then we know with certainty F = 2.
@@ -36,7 +36,7 @@ Example 3:
 
 Input: K = 3, N = 14
 Output: 4
- 
+
 
 Note:
 
@@ -52,82 +52,84 @@ Note:
 
 ## 思路
 
+> 本题已经重制，重制版更清晰 [《丢鸡蛋问题》重制版来袭～](https://lucifer.ren/blog/2020/06/08/887.super-egg-drop/)
+
 这是一道典型的动态规划题目，但是又和一般的动态规划不一样。
 
 拿题目给的例子为例，两个鸡蛋，六层楼，我们最少扔几次？
 
 ![887.super-egg-drop-1](../assets/problems/887.super-egg-drop-1.png)
 
-一个符合直觉的做法是，建立dp[i][j], 代表i个鸡蛋，j层楼最少扔几次，然后我们取dp[K][N]即可。
+一个符合直觉的做法是，建立 dp[i][j], 代表 i 个鸡蛋，j 层楼最少扔几次，然后我们取 dp[K][n]即可。
 
 代码大概这样的：
 
 ```js
- const dp = Array(K + 1);
-    dp[0] = Array(N + 1).fill(0);
-    for (let i = 1; i < K + 1; i++) {
-      dp[i] = [0];
-      for (let j = 1; j < N + 1; j++) {
-        // 只有一个鸡蛋
-        if (i === 1) {
-          dp[i][j] = j;
-          continue;
-        }
-        // 只有一层楼
-        if (j === 1) {
-          dp[i][j] = 1;
-          continue;
-        }
-
-        // 每一层我们都模拟一遍
-        const all = [];
-        for (let k = 1; k < j + 1; k++) {
-          const brokenCount = dp[i - 1][k - 1]; // 如果碎了
-          const notBrokenCount = dp[i][j - k]; // 如果没碎
-          all.push(Math.max(brokenCount, notBrokenCount)); // 最坏的可能
-        }
-        dp[i][j] = Math.min(...all) + 1; // 最坏的集合中我们取最好的情况
-      }
+const dp = Array(K + 1);
+dp[0] = Array(N + 1).fill(0);
+for (let i = 1; i < K + 1; i++) {
+  dp[i] = [0];
+  for (let j = 1; j < N + 1; j++) {
+    // 只有一个鸡蛋
+    if (i === 1) {
+      dp[i][j] = j;
+      continue;
+    }
+    // 只有一层楼
+    if (j === 1) {
+      dp[i][j] = 1;
+      continue;
     }
 
-    return dp[K][N];
+    // 每一层我们都模拟一遍
+    const all = [];
+    for (let k = 1; k < j + 1; k++) {
+      const brokenCount = dp[i - 1][k - 1]; // 如果碎了
+      const notBrokenCount = dp[i][j - k]; // 如果没碎
+      all.push(Math.max(brokenCount, notBrokenCount)); // 最坏的可能
+    }
+    dp[i][j] = Math.min(...all) + 1; // 最坏的集合中我们取最好的情况
+  }
+}
+
+return dp[K][N];
 ```
 
 果不其然，当我提交的时候，超时了。 这个的时复杂度是很高的，可以看到，我们内层暴力的求解所有可能，然后
-取最好的，这个过程非常耗时，大概是O(N^2 * K).
+取最好的，这个过程非常耗时，大概是 O(N^2 \* K).
 
-然后我看了一位leetcode[网友](https://leetcode.com/lee215/)的回答,
+然后我看了一位 leetcode[网友](https://leetcode.com/lee215/)的回答,
 他的想法是`dp[M][K]means that, given K eggs and M moves，what is the maximum number of floor that we can check.`
 
 我们按照他的思路重新建模：
 
 ![887.super-egg-drop-2](../assets/problems/887.super-egg-drop-2.png)
 
 可以看到右下角的部分根本就不需要计算，从而节省很多时间
-## 关键点解析
 
-- dp建模思路要发生变化, 即
-`dp[M][K]means that, given K eggs and M moves，what is the maximum number of floor that we can check.`
+## 关键点解析
 
+- dp 建模思路要发生变化, 即
+  `dp[M][K]means that, given K eggs and M moves，what is the maximum number of floor that we can check.`
 
 ## 代码
 
-
 ```js
 /**
  * @param {number} K
  * @param {number} N
  * @return {number}
  */
-var superEggDrop = function(K, N) {
+var superEggDrop = function (K, N) {
   // 不选择dp[K][M]的原因是dp[M][K]可以简化操作
-  const dp = Array(N + 1).fill(0).map(_ => Array(K + 1).fill(0))
-
+  const dp = Array(N + 1)
+    .fill(0)
+    .map((_) => Array(K + 1).fill(0));
+
   let m = 0;
   while (dp[m][K] < N) {
-      m++;
-      for (let k = 1; k <= K; ++k)
-          dp[m][k] = dp[m - 1][k - 1] + 1 + dp[m - 1][k];
+    m++;
+    for (let k = 1; k <= K; ++k) dp[m][k] = dp[m - 1][k - 1] + 1 + dp[m - 1][k];
   }
   return m;
 };