python - Retrieve the two highest item from a list containing 100,000 integers -

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how can retrieve 2 highest item list containing 100,000 integers without having sort entire list first?

in python, use heapq.nlargest. flexible approach in case ever want handle more top 2 elements.

here's example.

>>> import heapq >>> import random >>> x = range(100000) >>> random.shuffle(x) >>> heapq.nlargest(2, x) [99999, 99998]

documentation: http://docs.python.org/library/heapq.html#heapq.nlargest


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