#include<iostream> #include<cstdio> #include<cstring> #include<string> #include<cmath> #include<algorithm> #include<map> #include<set> #include<vector> #include<queue> #include<stack> //#in…

                                                                              Computer Transformation                                                                                   Time Limit: 2000/1000 MS (Java/Others)     Memory Limit: 65536/327…

题目链接: http://poj.org/problem?id=1737 题意: 求 \(n\) 个点的无向简单(无重边无自环)连通图的个数.\((n<=50)\) 题解: 这题你甚至能OEIS. http://oeis.org/A001187 但不支持这样做.TAT 间接做. 总方案数减去不合法方案. 因为\(n\)个点的完全图有 \(C(n,2)={n(n-1) \over 2}\) 条边,显然就有 \(2^{C(n,2)}\) 种子图,即枚举每条边是否选择. 设$ f[i]$ 表示每个点都…

https://vjudge.net/problem/UVA-10328 题意: 有H和T两个字符,现在要排成n位的字符串,求至少有k个字符连续的方案数. 思路:这道题目和ZOJ3747是差不多的,具体做法可以参考另一篇博客http://www.cnblogs.com/zyb993963526/p/7203833.html 但是这道题目的话是要用大数来做的,c++感觉不太好写,就学了下java的做法. import java.math.BigInteger; import java.util.S…

You will be given a string which only contains ‘1’; You can merge two adjacent ‘1’ to be ‘2’, or leave the ‘1’ there. Surly, you may get many different results. For example, given 1111 , you can get 1111, 121, 112,211,22. Now, your work is to find th…

Buy the Ticket Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 4185    Accepted Submission(s): 1759 Problem Description The "Harry Potter and the Goblet of Fire" will be on show in the next…

Description In how many ways can you tile a 2xn rectangle by 2x1 or 2x2 tiles? Here is a sample tiling of a 2x17 rectangle. Input Input is a sequence of lines, each line containing an integer number 0 <= n <= 250. Output For each line of input, outp…

题目链接: http://acm.hdu.edu.cn/showproblem.php?pid=1297 题目大意: 有n个同学, 站成一排, 要求 女生最少是两个站在一起, 问有多少种排列方式. 题目分析: 1.  假设第n个学生是个男生, 我们可以直接将他放在最后有 dp[n-1]种 即: ...............M   dp[n-1] 2.假设第n个放女生,要求两个女生在一起, 我们可以直接在最后放两个女生 即: .............FF    dp[n-2] 3.假设我们后面…

Description If we connect 3 numbers with "<" and "=", there are 13 cases: 1) A=B=C 2) A=B<C 3) A<B=C 4) A<B<C 5) A<C<B 6) A=C<B 7) B<A=C 8) B<A<C 9) B<C<A 10) B=C<A 11) C<A=B 12) C<A<B…

Computer Transformation Time Limit: 1000MS Memory Limit: 65536K Total Submissions: 4561 Accepted: 1738 Description A sequence consisting of one digit, the number 1 is initially written into a computer. At each successive time step, the computer simul…