2016年9月7日
Educational Codeforces Round 1 A
摘要： In this problem you are to calculate the sum of all integers from 1 to n, but you should take all powers of two with minus in the sum. For example, fo 阅读全文
posted @ 2016-09-07 22:21 樱花落舞 阅读(222) 评论(0) 推荐(0) 编辑