我是一个小乌龟

摘要： 原题地址：http://acm.hdu.edu.cn/showproblem.php?pid=1342部分题目： In a Lotto I have ever played, one has to select 6 numbers from the set {1,2,...,49}. A popular strategy to play Lotto - although it doesn't increase your chance of winning - is to select a subset S containing k (k>6) of these 49 number 阅读全文

摘要： 原题地址：http://acm.hdu.edu.cn/showproblem.php?pid=1128题目大意： In 1949 the Indian mathematician D.R. Kaprekar discovered a class of numbers called self-numbers. For any positive integer n, define d(n) to be n plus the sum of the digits of n. (The d stands for digitadition, a term coined by Kaprekar.) For. 阅读全文