Chess Club Standings

PandasMediumMid level~10 min

Problem

You are given two DataFrames. `players` has columns `player_id`, `player_name`. `games` has columns `white_id`, `black_id`, `white_score`, `black_score`; each row is one game (who played White, who played Black, and the rounds each side won).

Build the club standings. For each player report:
- `player_name`
- `games_played`
- `league_points`: Win = 3, Draw = 1, Loss = 0
- `rounds_for`: total rounds the player won
- `rounds_against`: total rounds the player conceded
- `rounds_diff`: `rounds_for` minus `rounds_against`

Return the columns in the order above, sorted by `league_points` DESC, then `rounds_diff` DESC, then `player_name` ASC.

Input data

Example rows — the live problem includes the full dataset.

players

player_id	player_name
1	Knight
2	Bishop
3	Rook

games

white_id	black_id	white_score	black_score
1	2	3	1
2	3	2	2
3	1	0	4

Expected output

Your answer should return 3 rows with the columns player_name, games_played, league_points, rounds_for, rounds_against, rounds_diff.

Starter code (Pandas (Python))

import pandas as pd

def chess_club_standings(players, games) -> pd.DataFrame:
    # Your code here
    return players

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