摘要：You have devised a new encryption technique which encodes a message by inserting between its characters randomly generated strings in a clever way. Be... 阅读全文

摘要：PuzzleA children's puzzle that was popular 30 years ago consisted of a 5x5 frame which contained 24 small squares of equal size. A unique letter of th... 阅读全文

摘要：= =听说是最水的动态规划，不过还是研究了挺长时间的，现在已经能熟练的做这类动规题了。大体思路就是每次第一次计算出MaxSum(i,j)的值时，把该值保存起来，以后再遇到MaxSum(i.j)时直接取出之前第一次调用时已经存放的值即可，不必再次调用MaxSum函数作递归计算。这样每个MaxSum(i... 阅读全文

摘要：= =用c做大数的题真是够够的了，跟着男神学了一下用Java做简单的加减乘除（即add，substract，multiply和divide），下面的代码是大数加法（多组输入）的代码。import java.math.BigInteger;import java.util.*;public class... 阅读全文

摘要：A character string is said to have period k if it can be formed by concatenating one or more repetitions of another string of length k. For example, t... 阅读全文