题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=5407 题目: Problem Description CRB has N different candies. He is going to eat K candies.He wonders how many combinations he can select.Can you answer his question for all K(0 ≤ K ≤ N)?CRB is too hungry to…
HDU5407 CRB and Candies 题意: 计算\(LCM(C(n,0),C(n,1),C(n,2),\cdots,C(n,n-1),C(n,n))\) \(n\le 10^6\) 题解: 规律: \(LCM(C(n,0),C(n,1),C(n,2),\cdots,C(n,n-1),C(n,n)) = \frac{LCM(1,2,3,\cdots,,n-1,n,n+1)}{n+1}\) 令\(g(n)=LCM(C(n,0),C(n,1),C(n,2),\cdots,C(n,n-1),…
[题目链接]pid=5407">click here~~ [题目大意]求LCM(Cn0,Cn1,Cn2....Cnn)%MOD 的值 [思路]来图更直观: 这个究竟是怎样推出的.说实话.本人数学归纳大法没有推出来,幸得一个大神给定愿文具体证明.点击这里:click here~~ 代码: #include <bits/stdc++.h> using namespace std; const int N=1e6+10; const int MOD=1e9+7; typedef lo…
CRB and Candies Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others)Total Submission(s): 722    Accepted Submission(s): 361 Problem Description CRB has N different candies. He is going to eat K candies.He wonders how ma…
题目 CRB and Candies 题意 \[ \text{给定正整数N,求} LCM \lbrace C \left(N , 0 \right),C\left(N , 1 \right),...,C\left(N , N \right) \rbrace \% mod \qquad 1\leq N \leq 10^6 \] 题解 根据规律推出公式,另外关于这个公式的证明 \[ LCM \lbrace C \left(N , 0 \right),C\left(N , 1 \right),...,…
题目:https://www.lydsy.com/JudgeOnline/problem.php?id=4591 这题不是很裸啊(所以我就不会了) 得稍微推导一下,看这个博客好了:https://blog.csdn.net/All_ice/article/details/68947444 以前求 1~n 的阶乘逆元一直是先用费马小定理求出 n! 的逆元,再每次 *i 递推回去: 这次用了另一种递推求阶乘逆元的方法,其实就是递推求逆元再阶乘起来:https://blog.csdn.net/w414…
题目链接: Hdu 5407 CRB and Candies 题目描述: 给出一个数n,求lcm(C(n,0),C[n,1],C[n-2]......C[n][n-2],C[n][n-1],C[n][n])%(1e9+7)是多少? 解题思路: 刚开始的时候各种开脑洞,然后卡题卡的风生水起.最后就上了数列查询这个神奇的网站,竟然被我找到了!!!!就是把题目上给的问题转化为求lcm(1, 2, 3, 4 ...... n-2, n-1, n, n-1) / (n+1),扎扎就打了两个表一个lcm[n…
pid=5407">[HDOJ 5407] CRB and Candies 赛后看这题题解仅仅有满眼的迷茫------ g(N) = LCM(C(N,0),C(N,1),...,C(N,N)) f(n)\ =\ LCM(1, 2, ..., n)f(n) = LCM(1,2,...,n), the fact g(n)\ =\ f(n+1) / (n+1)g(n) = f(n+1)/(n+1) f(n)\ =\ LCM(1, 2, ..., n)f(1) = 1 If n\ =p^{k}n …
CRB and Candies Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others)Total Submission(s): 453    Accepted Submission(s): 222 Problem Description   CRB has N different candies. He is going to eat K candies.He wonders how…
Codeforces Round #258 (Div. 2) Devu and Flowers E. Devu and Flowers time limit per test 4 seconds memory limit per test 256 megabytes input standard input output standard output Devu wants to decorate his garden with flowers. He has purchased n boxes…