一种优美而神奇的数论算法。
Codeforces Round #600 (Div. 2)题解。论如何会做五道题，比赛时做出四道，还FST两道。
Educational Codeforces Round 76 (Rated for Div. 2)题解。比赛链接
Codeforces Round #594 (Div. 2)题解。比赛地址
由于需要做一些特效，所以学了一下水波纹的生成算法。
Warm sunshine, cool wind and a fine day, while the girl watching is pursuing in chaos. Rikka reached out her hand and got the garland on her head, finding LCR with the immortal smile. The dream ended up waking, but the doubts will never disappear. In the end, without knowing about LCR, Rikka was invited to Shuyuan Men, a street of Chinese traditional arts in Xi’an.
难度：提高+/省选-
不算难，但是思想挺有意思的一题。
对于任意输入的正整数n，请编程求出具有n个不同因子的最小正整数m。
例如：n=4，则m=6，因为6有4个不同整数因子1,2,3,6；而且是最小的有4个因子的整数。