"""Boyer-Moore majority vote: element appearing > n/2 times, or None."""
from __future__ import annotations
from typing import Any, Iterable, Optional


def majority(nums: Iterable[Any]) -> Optional[Any]:
    arr = list(nums)
    cand = None
    count = 0
    for x in arr:
        if count == 0:
            cand = x
            count = 1
        elif x == cand:
            count += 1
        else:
            count -= 1
    if not arr:
        return None
    if arr.count(cand) > len(arr) // 2:
        return cand
    return None