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谵语In her bike rides around Warsaw, Jill happened upon a shop that sold interesting glass bottles. She thought it might make an interesting project to use such bottles for measuring liquids, but

用Java大数注意不能预处理组合数数组，会爆内存，

题目链接：http://acm.bnu.edu.cn/v3/problem_show.php?pid=7931分析：    求一个数n(n    直接for找因子一个个判断的话复杂度为10^9,太慢。    一个很好的方法：        分3种情况：            1. n = k^2 (k            2. n/i = k^2 (k