2013 年 5月 18 日随笔档案 - 木-天空

2013年5月18日

codeforces 285 D Permutation Sum (状态压缩DP)

摘要：题目链接： http://www.codeforces.com/problemset/problem/285/DPermutation p is an ordered set of integers p1, p2, ..., pn, consisting of n distinct positive integers, each of them doesn't exceed n. We'll denote the i-th element of permutation p as pi. We'll call number n the size or the length 阅读全文

posted @ 2013-05-18 16:05 木-天空阅读(724) 评论(0) 推荐(0)

codeforces 300 C Beautiful Numbers 逆元的运用

摘要：题目链接： www.codeforces.com/problemset/problem/300/CVitaly is a very weird man. He's got two favorite digits a and b. Vitaly calls a positive integer good, if the decimal representation of this integer only contains digits a and b. Vitaly calls a good number excellent, if the sum of its digits is a 阅读全文

posted @ 2013-05-18 11:29 木-天空阅读(407) 评论(0) 推荐(0)

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