Codewars 6 kyu Highest Rank Number in an Array

Task

Complete the method which returns the number which is most frequent in the given input array. If there is a tie for most frequent number, return the largest number among them.

Verbalization

1. 各数字の出現回数を数える
2. 最頻値を探す（回数が最大のもの）

Code

from collections import Counter
def highest_rank(arr):
    counts = Counter(arr)
    max_count = max(counts.values())

    candidates = []
    for num, cnt in counts.items():
        if cnt == max_count:
            candidates.append(num)
    
    return max(candidates)

Reference

出現回数を数えるのは、collections.Counterが便利（from collections import Counter）
辞書の値として値が保存される
https://docs.python.org/ja/3.13/library/collections.html#collections.Counter