+; int prime[maxn]; void marktable(int n){ memset(prime,,sizeof(prime)); ;i<=n;i++){ ]]=i; ;j<=prime[]&&prime[j]<=n/i;j++){ prime[prime[j]*i]=; ) break; } } } ][]; int fatCnt; int getFactors(long long x){ fatCnt=; long long tmp=x; ;prime[…
import java.util.ArrayList; import java.util.List; //一个数如果恰好等于它的因子之和,这个数就称为"完数".例如6=1+2+3.第二个完全数是28, //它有约数1.2.4.7.14.28,除去它本身28外,其余5个数相加, //编程找出1000以内的所有完数. public class Test { public static void main(String[] args) { System.out.print("完数有…
day12 --------------------------------------------------------------- 实例019:完数 题目 一个数如果恰好等于它的因子之和,这个数就称为"完数".例如6=1+2+3.编程找出1000以内的所有完数. 分析:如果能被a整除,那么a是因子,放入一个列表然后再求和,与原被除数相等,就是完数 1 for i in range(1,int(a)): 2 list = [] 3 if i >1: 4 for j in r…
Sumdiv Time Limit:1000MS Memory Limit:30000KB 64bit IO Format:%I64d & %I64u Submit Status Practice POJ 1845 Appoint description: System Crawler (2015-05-27) Description Consider two natural numbers A and B. Let S be the sum of all natural…
ISSN Abbreviated Journal Title Full Title Category Subcategory Country total Cites IF 2013-2014 IF 2012-2013 IF 2011-2012 IF 2010-2011 IF 2009-2010 IF 2008-2009 IF 2007-2008 5-Year Impact Factor Immediacy Index Articles Cited Half-Life Eigenfa…
a.b只要数字a能被数字b整除,不论b是不是质数,都算是a的因子.比如:8的质因子是 2, 2, 2,但8的因子就包括 1,2,4. import math for i in range(2, 1000): factors = [] #因子列表,i 每次循环都清空 for j in range(1, math.floor(i/2)+1): if i%j == 0: factors.append(j) if sum(factor…
题意:给出一大数K(4 <= K <= 10^100)与一整数L(2 <= L <= 106),K为两个素数的乘积(The cryptographic keys are created from the product of two primes) 问构成K的最小素数是否绝对小于L,若是,则输出BAD p,p为最小素数,否则输出GOOD; 分析:从小到大枚举1~10^6内的素数p,while(p<L)时,判断K是否能被p整除,若能则证明构成K的最小素数绝对小于L,反之则大于L…
n对mod求模,它的值在0到mod-1之间,如果要求模整除的时候转化成mod可以用下面的式子: n = (n - 1 % mod + mod) % mod +1 这里先减一,模上mod再加一,这样如果是整除mod的话先减一模上之后就变成mod-1,最后+1就变成mod了 这里模mod的方法是先模mod再加mod再模mod,这是常用的做法,目的是为了使得模的结过为正数,而不是负数.…
先放知识点: 莫比乌斯反演 卢卡斯定理求组合数 乘法逆元 快速幂取模 GCD of Sequence Alice is playing a game with Bob. Alice shows N integers a 1, a 2, -, a N, and M, K. She says each integers 1 ≤ a i ≤ M. And now Alice wants to ask for each d = 1 to M, how many different sequences b…
The Children's Day has passed for some days .Has you remembered something happened at your childhood? I remembered I often played a game called hide handkerchief with my friends. Now I introduce the game to you. Suppose there are N people played the…
