A. Puzzles 对\(f[]\)排序,取连续的\(m\)个。B. Routine Problem 考虑\(\frac{a}{b}\)和\(\frac{c}{d}\)的大小关系,适配后就是分数的运算。C. Quiz 按\(k\)将\(n\)个问题分段,那么在没有分数翻倍的情况下最大题数为\[(k-1)\lfloor\frac{n}{k}\rfloor
cf劲啊 原题: We have a string of letters 'a' and 'b'. We want to perform some operations on it. On each step we choose one of substrings "ab" in the string and replace it with the string "bba". If we have no "ab&