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#!/usr/bin/env python3
from collections import Counter
def lucky_integer(*integers):
""" Given an array of integers, return the lucky integer if found otherwise
return -1. If there are more than one then return the largest.
A lucky integer is an integer that has a frequency in the array equal
to its value.
>>> lucky_integer(2, 2, 3, 4)
2
>>> lucky_integer(1, 2, 2, 3, 3, 3)
3
>>> lucky_integer(1, 1, 1, 3)
-1
"""
counter = Counter(integers)
return max((i for i, v in counter.items() if i == v), default=-1)
if __name__ == "__main__":
import doctest
doctest.testmod(verbose=True)
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