Hopper Company Queries II — LeetCode 1645 Python Solution

HardLeetCode PremiumDatabase
Problem
#1645
Reading time
8 min

Table schema

SQL
Table: Drivers +-------------+---------+ | Column Name | Type | +-------------+---------+ | driver_id | int | | join_date | date | +-------------+---------+ driver_id is the column with unique values for this table. Each row of this table contains the driver's ID and the date they joined the Hopper company.

Example

SQL
+-------------+---------+
| Column Name | Type    |
+-------------+---------+
| driver_id   | int     |
| join_date   | date    |
+-------------+---------+
driver_id is the column with unique values for this table.
Each row of this table contains the driver's ID and the date they joined the Hopper company.

Python solution

Python
import duckdb
import pandas as pd

def solution(drivers: pd.DataFrame, rides: pd.DataFrame, accepted_rides: pd.DataFrame) -> pd.DataFrame:
    con = duckdb.connect()
    con.register("Drivers", drivers)
    con.register("Rides", rides)
    con.register("AcceptedRides", accepted_rides)
    return con.execute("""WITH RECURSIVE
    Month AS (
        SELECT 1 AS month
        UNION
        SELECT month + 1
        FROM Month
        WHERE month < 12
    ),
    S AS (
        SELECT month, driver_id, join_date
        FROM
            Month AS m
            LEFT JOIN Drivers AS d
                ON YEAR(d.join_date) < 2020
                OR (YEAR(d.join_date) = 2020 AND MONTH(d.join_date) <= month)
    ),
    T AS (
        SELECT driver_id, requested_at
        FROM
            Rides
            JOIN AcceptedRides USING (ride_id)
        WHERE YEAR(requested_at) = 2020
    )
SELECT
    month,
    IFNULL(
        ROUND(COUNT(DISTINCT t.driver_id) * 100 / COUNT(DISTINCT s.driver_id), 2),
        0
    ) AS working_percentage
FROM
    S AS s
    LEFT JOIN T AS t
        ON s.driver_id = t.driver_id
        AND s.join_date <= t.requested_at
        AND s.month = MONTH(t.requested_at)
GROUP BY 1;""").df()

Complexity

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

Related problems

Frequently asked questions

How hard is LeetCode 1645. Hopper Company Queries II?
LeetCode 1645. Hopper Company Queries II is rated Hard on LeetCode.
What topics does LeetCode 1645. Hopper Company Queries II cover?
LeetCode 1645. Hopper Company Queries II is tagged Database on LeetCode.
Is LeetCode 1645. Hopper Company Queries II a premium problem?
Yes. LeetCode 1645. Hopper Company Queries II is a LeetCode Premium problem, so the full statement and test cases require a paid LeetCode subscription.

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