Election Results — LeetCode 2820 Python Solution

Table: Votes +-------------+---------+ | Column Name | Type | +-------------+---------+ | voter | varchar | | candidate | varchar | +-------------+---------+ (voter, candidate) is the primary key (combination of unique values) for this table. Each row of this table contains name of the voter and their candidate.

+-------------+---------+ 
| Column Name | Type    | 
+-------------+---------+ 
| voter       | varchar | 
| candidate   | varchar |
+-------------+---------+
(voter, candidate) is the primary key (combination of unique values) for this table.
Each row of this table contains name of the voter and their candidate.

import duckdb
import pandas as pd

# Pass input tables as keyword arguments matching the SQL table names.
def solution(**tables) -> pd.DataFrame:
    con = duckdb.connect()
    for name, df in tables.items():
        con.register(name, df)
    return con.execute("""WITH
    T AS (
        SELECT candidate, SUM(vote) AS tot
        FROM
            (
                SELECT
                    candidate,
                    1 / (COUNT(candidate) OVER (PARTITION BY voter)) AS vote
                FROM Votes
                WHERE candidate IS NOT NULL
            ) AS t
        GROUP BY 1
    ),
    P AS (
        SELECT
            candidate,
            RANK() OVER (ORDER BY tot DESC) AS rk
        FROM T
    )
SELECT candidate
FROM P
WHERE rk = 1
ORDER BY 1;""").df()