10.3 Given an input file with four billion non-negative integers, provide an algorithm to generate an integer which is not contained in the file. Assume you have 1 GB of memory available for this task.
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What if you have only 10 MB of memory? Assume that all the values are distinct and we now have no more than one billion non-negative integers.
[CareerCup] 10.3 Integer not Contain in the File 文件中不包含的数
原文：http://www.cnblogs.com/grandyang/p/4855652.html