Happy 2004 Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others) Total Submission(s): 2183    Accepted Submission(s): 1582 Problem Description Consider a positive integer X,and let S be the sum of all positive integer di…

题目不难懂.式子是一个递推式,并且不难发现f[n]都是a的整数次幂.(f[1]=a0;f[2]=ab;f[3]=ab*f[2]c*f[1]...) 我们先只看指数部分,设h[n]. 则 h[1]=0; h[2]=b; h[3]=b+h[2]*c+h[1]; h[n]=b+h[n-1]*c+h[n-1]. h[n]式三个数之和的递推式,所以就可以转化为3x3的矩阵与3x1的矩阵相乘.于是 h[n] c  1  b h[n-1] h[n-1] = 1  0  0 * h[n-2] 1       0…

题目链接 题意 : m张牌,可以翻n次,每次翻xi张牌,问最后能得到多少种形态. 思路 :0定义为反面,1定义为正面,(一开始都是反), 对于每次翻牌操作,我们定义两个边界lb,rb,代表每次中1最少时最少的个数,rb代表1最多时的个数.一张牌翻两次和两张牌翻一次 得到的奇偶性相同,所以结果中lb和最多的rb的奇偶性相同.如果找到了lb和rb,那么,介于这两个数之间且与这两个数奇偶性相同的数均可取到,然后在这个区间内求组合数相加(若lb=3,rb=7,则3,5,7这些情况都能取到,也就是说最后的…

Problem Description During summer vacation,Alice stay at home for a long time, with nothing to do. She went out and bought m pokers, tending to play poker. But she hated the traditional gameplay. She wants to change. She puts these pokers face down,…

Sequence Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others) Total Submission(s): 1424    Accepted Submission(s): 469 Problem Description     Holion August will eat every thing he has found. Now there are many foods,bu…

Sum Time Limit:1000MS     Memory Limit:131072KB     64bit IO Format:%I64d & %I64u Submit Status Practice HDU 4704 Description   Sample Input 2   Sample Output 2 Hint 1. For N = 2, S(1) = S(2) = 1. 2. The input file consists of multiple test cases. 题意…

Ignatius's puzzle Problem Description Ignatius is poor at math,he falls across a puzzle problem,so he has no choice but to appeal to Eddy. this problem describes that:f(x)=5x13+13*x5+ka*x,input a nonegative integer k(k<10000),to find the minimal none…

Description Consider a positive integer X,and let S be the sum of all positive integer divisors of 2004^X. Your job is to determine S modulo 29 (the rest of the division of S by 29). Take X = 1 for an example. The positive integer divisors of 2004^1…

Sum Problem's Link:   http://acm.hdu.edu.cn/showproblem.php?pid=4704 Mean: 给定一个大整数N,求1到N中每个数的因式分解个数的总和. analyse: N可达10^100000,只能用数学方法来做. 首先想到的是找规律.通过枚举小数据来找规律,发现其实answer=pow(2,n-1); 分析到这问题就简单了.由于n非常大,所以这里要用到费马小定理:a^n ≡ a^(n%(m-1)) * a^(m-1)≡ a^(n%(m-…

题目传送:http://acm.hdu.edu.cn/showproblem.php?pid=4704 Problem Description   Sample Input 2 Sample Output 2 Hint 1. For N = 2, S(1) = S(2) = 1. 2. The input file consists of multiple test cases.   题意是输入一个N,求N被分成1个数的结果+被分成2个数的结果+...+被分成N个数的结果,N很大   1.隔板原…