League Statistics — LeetCode 1841 Python Solution

MediumLeetCode PremiumDatabase
Problem
#1841
Reading time
8 min

Table schema

SQL
Table: Teams +----------------+---------+ | Column Name | Type | +----------------+---------+ | team_id | int | | team_name | varchar | +----------------+---------+ team_id is the column with unique values for this table. Each row contains information about one team in the league.

Example

SQL
+----------------+---------+
| Column Name    | Type    |
+----------------+---------+
| team_id        | int     |
| team_name      | varchar |
+----------------+---------+
team_id is the column with unique values for this table.
Each row contains information about one team in the league.

Python solution

Python
import duckdb
import pandas as pd

def solution(teams: pd.DataFrame, matches: pd.DataFrame) -> pd.DataFrame:
    con = duckdb.connect()
    con.register("Teams", teams)
    con.register("Matches", matches)
    return con.execute("""WITH
    Scores AS (
        SELECT
            home_team_id AS team_id,
            CASE
                WHEN home_team_goals > away_team_goals THEN 3
                WHEN home_team_goals < away_team_goals THEN 0
                ELSE 1
            END AS score,
            home_team_goals AS goals,
            away_team_goals AS away_goals
        FROM Matches
        UNION ALL
        SELECT
            away_team_id AS team_id,
            CASE
                WHEN home_team_goals > away_team_goals THEN 0
                WHEN home_team_goals < away_team_goals THEN 3
                ELSE 1
            END AS score,
            away_team_goals AS goals,
            home_team_goals AS away_goals
        FROM Matches
    )
SELECT
    team_name,
    COUNT(1) AS matches_played,
    SUM(score) AS points,
    SUM(goals) AS goal_for,
    SUM(away_goals) AS goal_against,
    (SUM(goals) - SUM(away_goals)) AS goal_diff
FROM
    Scores AS s
    JOIN Teams AS t ON s.team_id = t.team_id
GROUP BY s.team_id
ORDER BY points DESC, goal_diff DESC, team_name;""").df()

Complexity

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

Related problems

Frequently asked questions

How hard is LeetCode 1841. League Statistics?
LeetCode 1841. League Statistics is rated Medium on LeetCode.
What topics does LeetCode 1841. League Statistics cover?
LeetCode 1841. League Statistics is tagged Database on LeetCode.
Is LeetCode 1841. League Statistics a premium problem?
Yes. LeetCode 1841. League Statistics is a LeetCode Premium problem, so the full statement and test cases require a paid LeetCode subscription.

Stuck on problems like this in a live interview?

Stealth Interview is a desktop app for macOS and Windows. It reads the problem off your screen and returns a working solution with a step-by-step explanation and its time and space complexity — invisible to screen sharing.

Get Stealth Interview