"content":"<p>Table: <code>Stocks</code></p>\n\n<pre>\n+---------------+---------+\n| Column Name | Type |\n+---------------+---------+\n| stock_name | varchar |\n| operation | enum |\n| operation_day | int |\n| price | int |\n+---------------+---------+\n(stock_name, operation_day) is the primary key for this table.\nThe operation column is an ENUM of type ('Sell', 'Buy')\nEach row of this table indicates that the stock which has stock_name had an operation on the day operation_day with the price.\nIt is guaranteed that each 'Sell' operation for a stock has a corresponding 'Buy' operation in a previous day. It is also guaranteed that each 'Buy' operation for a stock has a corresponding 'Sell' operation in an upcoming day.\n</pre>\n\n<p> </p>\n\n<p>Write an SQL query to report the <strong>Capital gain/loss</strong> for each stock.</p>\n\n<p>The <strong>Capital gain/loss</strong> of a stock is the total gain or loss after buying and selling the stock one or many times.</p>\n\n<p>Return the result table in <strong>any order</strong>.</p>\n\n<p>The query result format is in the following example.</p>\n\n<p> </p>\n<p><strong>Example 1:</strong></p>\n\n<pre>\n<strong>Input:</strong> \nStocks table:\n+---------------+-----------+---------------+--------+\n| stock_name | operation | operation_day | price |\n+---------------+-----------+---------------+--------+\n| Leetcode | Buy | 1 | 1000 |\n| Corona Masks | Buy | 2 | 10 |\n| Leetcode | Sell | 5 | 9000 |\n| Handbags | Buy | 17 | 30000 |\n| Corona Masks | Sell | 3 | 1010 |\n| Corona Masks | Buy | 4 | 1000 |\n| Corona Masks | Sell | 5 | 500 |\n| Corona Masks | Buy | 6 | 1000 |\n| Handbags | Sell | 29 | 7000 |\n| Corona Masks | Sell | 10 | 10000 |\n+---------------+-----------+---------------+--------+\n<strong>Output:</strong> \n+---------------+-------------------+\n| stock_name | capital_gain_loss |\n+---------------+-------------------+\n| Corona Masks | 9500 |\n| Leetcode | 8000 |\n| Handbags | -23000 |\n+---------------+-------------------+\n<strong>Explanation:</strong> \nLeetcode stock was bought at day 1 for 1000$ and was sold at day 5 for 9000$. Capital gain = 9000 - 1000 = 8000$.\nHandbags stock was bought at day 17 for 30000$ and was sold at day 29 for 7000$. Capital loss = 7000 - 30000 = -23000$.\nCorona Masks stock was bought at day 1 for 10$ and was sold at day 3 for 1010$. It was bought again at day 4 for 1000$ and was sold at day 5 for 500$. At last, it was bought at day 6 for 1000$ and was sold at day 10 for 10000$. Capital gain/loss is the sum of capital gains/losses for each ('Buy' --> 'Sell') operation = (1010 - 10) + (500 - 1000) + (10000 - 1000) = 1000 - 500 + 9000 = 9500$.\n</pre>\n",
