codeforces 336D. Vasily the Bear and Beautiful Strings 组合数学 dp

【codeforces 336D. Vasily the Bear and Beautiful Strings 组合数学 dp】的更多相关文章

codeforces 336D. Vasily the Bear and Beautiful Strings 组合数学 dp

题意: 给出n,m,g,求好串的个数 0 <= n,m <= 10^5,n + m >= 1,0 <= g <= 1 好串的定义: 1.只由0,1组成,并且恰好有n个0,m个1 2.串的value = g 串的value的计算方式: 每次将最后2个字符替换,直至串的长度为1,该字符就是串的value 00 -> 1, 01,11,10 -> 0 solution: 首先,总方案数 = C(n + m, m) m = 0时,特殊判断设f(n,m)为n个0,m个…

codeforces 336D Vasily the Bear and Beautiful Strings(组合数学)

转载请注明出处: http://www.cnblogs.com/fraud/ ——by fraud Vasily the Bear and Beautiful Strings Vasily the Bear loves beautiful strings. String s is beautiful if it meets the following criteria: String s only consists of characters 0 and 1, at that…

Codeforces Round #195 (Div. 2) D题Vasily the Bear and Beautiful Strings

这场CF,脑子乱死啊...C题,搞了很长时间,结束了,才想到怎么做.B题,没看,D题,今天看了一下,很不错的组合题. 如果n和m都挺多的时候以下情况都是变为1,根据偶数个0,最后将会为1,奇数个0,最后变为0,以1开头,全都是0. 0 1.. 0 0 0 1.... 0 0 0 0 0 1.... 总的情况是C(n+m,m),算1也可以算出来.注意m = 1的时候特判,0的时候,我也全写的特判. 10^5的组合数,用费马小定理求逆元.看了下题解,题解直接来了个逆元.. inv(a) = a^(…

codeforces 336C Vasily the Bear and Sequence(贪心)

转载请注明出处: http://www.cnblogs.com/fraud/ ——by fraud Vasily the Bear and Sequence Vasily the bear has got a sequence of positive integers a1, a2, ..., an. Vasily the Bear wants to write out several numbers on a piece of paper so that the beauty…

codeforces C. Vasily the Bear and Sequence 解题报告

题目链接:http://codeforces.com/problemset/problem/336/C 题目意思:给出一个递增的正整数序列 a1, a2, ..., an,要求从中选出一堆数b1, b2, ..., bk,这堆数进行完按位&运算之后(b1 and b2 and ... and bk),能被2v整除.除此,还要求所选中的这堆数是两两不同的,&之后要最大,换句话来说,v 要尽可能最大,如果找到最大的v的方法有多种,即在 a1, a2, ..., an 中有很多种不同的组合 &a…

codeforces A. Vasily the Bear and Triangle 解题报告

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C. Vasily the Bear and Sequence Codeforces 336C(枚举，思维)

C. Vasily the Bear and Sequence time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Vasily the bear has got a sequence of positive integers a1, a2, ..., *a**n*. Vasily the Bear wants to write o…