Capital Gain/Loss — LeetCode 1393 Python Solution

MediumDatabase
Problem
#1393
Reading time
3 min

Table schema

SQL
Table: Stocks +---------------+---------+ | Column Name | Type | +---------------+---------+ | stock_name | varchar | | operation | enum | | operation_day | int | | price | int | +---------------+---------+ (stock_name, operation_day) is the primary key (combination of columns with unique values) for this table. The operation column is an ENUM (category) of type ('Sell', 'Buy') Each row of this table indicates that the stock which has stock_name had an operation on the day operation_day with the price.

Example

SQL
+---------------+---------+
| Column Name   | Type    |
+---------------+---------+
| stock_name    | varchar |
| operation     | enum    |
| operation_day | int     |
| price         | int     |
+---------------+---------+
(stock_name, operation_day) is the primary key (combination of columns with unique values) for this table.
The operation column is an ENUM (category) of type ('Sell', 'Buy')
Each row of this table indicates that the stock which has stock_name had an operation on the day operation_day with the price.
It 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.

Python solution

Python
import duckdb
import pandas as pd

def solution(stocks: pd.DataFrame) -> pd.DataFrame:
    con = duckdb.connect()
    con.register("Stocks", stocks)
    return con.execute("""SELECT
    stock_name,
    SUM(IF(operation = 'Buy', -price, price)) AS capital_gain_loss
FROM Stocks
GROUP BY 1;""").df()

Complexity

MeasureComplexity
TimeO(n log n) (typical)
SpaceO(n) auxiliary

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Frequently asked questions

How hard is LeetCode 1393. Capital Gain/Loss?
LeetCode 1393. Capital Gain/Loss is rated Medium on LeetCode.
What topics does LeetCode 1393. Capital Gain/Loss cover?
LeetCode 1393. Capital Gain/Loss is tagged Database on LeetCode.

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