add code

Author: ncdhz

code/123.买卖股票的最佳时机-iii.java

@@ -7,7 +7,17 @@
 // @lc code=start
 class Solution {
     public int maxProfit(int[] prices) {
-        
+        int buy1 = -prices[0];
+        int buy2 = -prices[0];
+        int sell1 = 0;
+        int sell2 = 0;
+        for (int i = 1; i < prices.length; i++) {
+            buy1 = Math.max(buy1, -prices[i]);
+            sell1 = Math.max(sell1, buy1 + prices[i]);
+            buy2 = Math.max(buy2, sell1 - prices[i]);
+            sell2 = Math.max(sell2, buy2 + prices[i]);
+        }
+        return sell2;
     }
 }
 // @lc code=end

code/174.地下城游戏.java

@@ -0,0 +1,14 @@
+/*
+ * @lc app=leetcode.cn id=174 lang=java
+ *
+ * [174] 地下城游戏
+ */
+
+// @lc code=start
+class Solution {
+    public int calculateMinimumHP(int[][] dungeon) {
+
+    }
+}
+// @lc code=end
+

code/175.组合两个表.sql

@@ -0,0 +1,11 @@
+--
+-- @lc app=leetcode.cn id=175 lang=mysql
+--
+-- [175] 组合两个表
+--
+
+-- @lc code=start
+# Write your MySQL query statement below
+select firstName, lastName, city, state from Person left join Address on Person.PersonId = Address.PersonId
+-- @lc code=end
+

code/176.第二高的薪水.sql

@@ -0,0 +1,11 @@
+--
+-- @lc app=leetcode.cn id=176 lang=mysql
+--
+-- [176] 第二高的薪水
+--
+
+-- @lc code=start
+# Write your MySQL query statement below
+select ifnull((select max(salary) from Employee where salary < (select max(salary) from Employee)), NULL) as SecondHighestSalary;
+-- @lc code=end
+

web/src/config.ts

@@ -52,6 +52,9 @@ export default {
     go: {
       name: "Go",
     },
+    sql: {
+      name: "SQL"
+    }
   },
   itemSpace: 10,
   menuSpace: 5,