Pseudoprime numbers(POJ 3641 快速幂)】的更多相关文章

#include <cstring> #include <cstdio> #include <iostream> #include <cmath> #include <algorithm> using namespace std; #define LL long long LL p,res,a; bool judge_prime(LL k) { LL i; LL u=int(sqrt(k*1.0)); ;i<=u;i++) { ) ; }…
http://poj.org/problem?id=3641 练手用,结果念题不清,以为是奇偶数WA了一发 #include<iostream> #include<cstdio> #include<cmath> using namespace std; typedef long long ll; bool judge_prime(ll k) { ll i; ll u=int(sqrt(k*1.0)); ;i<=u;i++) { ) ; } ; } ll mod_p…
Description Fermat's theorem states that for any prime number p and for any integer a > 1, ap = a (mod p). That is, if we raise a to the pth power and divide by p, the remainder is a. Some (but not very many) non-prime values of p, known as base-a ps…
 强伪素数 题目大意:利用费马定理找出强伪素数(就是本身是合数,但是满足费马定理的那些Carmichael Numbers) 很简单的一题,连费马小定理都不用要,不过就是要用暴力判断素数的方法先确定是不是素数,然后还有一个很重要的问题,那就是a和p是不互质的,不要用a^(p-1)=1(mod p)这个判据,比如4^6=4(mod 6),但是4^5=4(mod 6) #include <iostream> #include <functional> #include <algo…
Raising Modulo Numbers Time Limit: 1000MS   Memory Limit: 30000K Total Submissions: 5934   Accepted: 3461 Description People are different. Some secretly read magazines full of interesting girls' pictures, others create an A-bomb in their cellar, oth…
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…
http://poj.org/problem?id=1995 简单的快速幂问题 要注意num每次加过以后也要取余,否则会出问题 #include<iostream> #include<cstdio> using namespace std; typedef long long ll; ll mod_pow(ll x,ll n,ll mod) { ll res=; ) { ) res=res*x%mod; x=x*x%mod; n>>=; } return res; }…
  Carmichael Numbers  An important topic nowadays in computer science is cryptography. Some people even think that cryptography is the only important field in computer science, and that life would not matter at all without cryptography. Alvaro is one…
题目描述: 请输出(3+√5)^n整数部分最后3位.如果结果不超过2位,请补足前导0. 分析: 我们最容易想到的方法肯定是直接计算这个表达式的值,但是这样的精度是不够的.朴素的算法没有办法得到答案.但是我们根据分析可以发现这个问题不用求出√5的值也可以得到答案. 我们可以发现,将(3+√5)^n这个式子展开后就是An+Bn√5的形式.同样的,我们将(3-√5)^n这个式子展开后就是An-Bn√5. 因此,(3+√5)^n+(3-√5)^n=2An是一个整数,其中0<(3-√5)^n <1,是解…
题意:给出A1,…,AH,B1,…,BH以及M,求(A1^B1+A2^B2+ … +AH^BH)mod M. 思路:快速幂 实例 3^11  11=2^0+2^1+2^3    => 3^1*3^2*3^8=3^11 实现代码: int solve(int a,int b) { int ans=1;          while(b){ if(b&1)  ans=ans*a;   a=a*a;  b>>=1;} } 解释一下代码:b&1即二进制表达式的最后一位,  11二…
链接:传送门 题意:给一个 n ,输出 Fibonacci 数列第 n 项,如果第 n 项的位数 >= 8 位则按照 前4位 + ... + 后4位的格式输出 思路: n < 40时位数不会超过8位,直接打表输出 n >= 40 时,需要解决两个问题 后 4 位可以用矩阵快速幂求出,非常简单 前 4 位的求法借鉴 此博客! balabala:真是涨姿势了-- /****************************************************************…
题意:       给你一个无向图,然后给了一个起点s和终点e,然后问从s到e的最短路是多少,中途有一个限制,那就是必须走k条边,路径可以反复走. 思路:       感觉很赞的一个题目,据说证明是什么国家队集训队论文什么的,自己没去看那个论文,就说下我自己的理解吧,对于这个题目,我们首先分析下Floyd,那个算法的过程中是在更新的dis[i][j]上再更新,再更新...,是想一下,我们每次都把更新的结果存下来,就是每次答案数组初始化全是INF,然后用当前的dis数组和原始的map来更新,那么更…
Problem C. Numbers This contest is open for practice. You can try every problem as many times as you like, though we won't keep track of which problems you solve. Read the Quick-Start Guide to get started. Small input 15 points Solve C-small   Large…
Description People are different. Some secretly read magazines full of interesting girls' pictures, others create an A-bomb in their cellar, others like using Windows, and some like difficult mathematical games. Latest marketing research shows, that…
https://vjudge.net/problem/UVA-11582 首先明确,斐波那契数列在模c的前提下是有循环节的.而f[i] = f[i-1]+f[i-2](i>=2)所以只要有两个连续的值和开头的一样,后面就开始循环,两两组合共有c*c种. 找到循环节之后 #include<iostream> #include<cstdio> #include<cstring> #include<algorithm> #include<cstdlib…
题目链接:POJ 3641 Description Fermat's theorem states that for any prime number p and for any integer a > 1, ap = a (mod p). That is, if we raise a to the pth power and divide by p, the remainder is a. Some (but not very many) non-prime values of p, know…
Pseudoprime numbers Descriptions 费马定理指出,对于任意的素数 p 和任意的整数 a > 1,满足 ap = a (mod p) .也就是说,a的 p 次幂除以 p 的余数等于 a .p 的某些 (但不是很多) 非素数的值,被称之为以 a 为底的伪素数,对于某个 a 具有该特性.并且,某些 Carmichael 数,对于全部的 a 来说,是以 a为底的伪素数. 给定 2 < p ≤ 1000000000 且 1 < a < p ,判断 p 是否为以 …
Pseudoprime numbers Time Limit: 1000MS Memory Limit: 65536K Total Submissions: 7954 Accepted: 3305 Description Fermat's theorem states that for any prime number p and for any integer a > 1, ap = a (mod p). That is, if we raise a to the pth power and…
Pseudoprime numbers Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 11336   Accepted: 4891 Description Fermat's theorem states that for any prime number p and for any integer a > 1, ap = a (mod p). That is, if we raise a to the pth power…
题目连接 http://poj.org/problem?id=3641 Pseudoprime numbers Description Fermat's theorem states that for any prime number p and for any integer a > 1, ap = a (mod p). That is, if we raise a to the pth power and divide by p, the remainder is a. Some (but…
POJ3641 Pseudoprime numbers p是Pseudoprime numbers的条件: p是合数,(p^a)%p=a;所以首先要进行素数判断,再快速幂. 此题是大白P122 Carmichael Number 的简化版 /* * Created: 2016年03月30日 22时32分15秒 星期三 * Author: Akrusher * */ #include <cstdio> #include <cstdlib> #include <cstring&g…
Pseudoprime numbers Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 10903   Accepted: 4710 Description Fermat's theorem states that for any prime number p and for any integer a > 1, ap = a (mod p). That is, if we raise a to the pth power…
Fermat's theorem states that for any prime number p and for any integer a > 1, ap = a (mod p). That is, if we raise a to the pth power and divide by p, the remainder is a. Some (but not very many) non-prime values of p, known as base-a pseudoprimes,…
Raising Modulo Numbers Time Limit: 1000MS Memory Limit: 30000K Total Submissions: 9512 Accepted: 5783 Description People are different. Some secretly read magazines full of interesting girls' pictures, others create an A-bomb in their cellar, others…
题目链接:http://poj.org/problem?id=1995 解题思路:用整数快速幂算法算出每一个 Ai^Bi,然后依次相加取模即可. #include<stdio.h> long long quick_mod(long long a,long long b,long long c) { long long ans=1; while(b) { if(b&1) { ans=ans*a%c; } b>>=1; a=a*a%c; } return ans; } int…
-->Raising Modulo Numbers Descriptions: 题目一大堆,真没什么用,大致题意 Z M H A1  B1 A2  B2 A3  B3 ......... AH  BH 有Z组数据   求(A1B1+A2B2+ ... +AHBH)mod M. Sample Input 3 16 4 2 3 3 4 4 5 5 6 36123 1 2374859 3029382 17 1 3 18132 Sample Output 2 13195 13 题目链接https://v…
嗯... 题目链接:http://poj.org/problem?id=1995 快速幂模板... AC代码: #include<cstdio> #include<iostream> using namespace std; int main(){ ; scanf("%lld", &N); while(N--){ scanf("%lld%lld", &M, &n); sum = ; ; i <= n; i++){…
Raising Modulo Numbers Time Limit: 1000MS   Memory Limit: 30000K Total Submissions: 5532   Accepted: 3210 Description People are different. Some secretly read magazines full of interesting girls' pictures, others create an A-bomb in their cellar, oth…
输入a和p.如果p不是素数,则若满足ap = a (mod p)输出yes,不满足或者p为素数输出no.最简单的快速幂,啥也不说了. #include<iostream> #include<cstdio> #include<cstring> #include<cmath> using namespace std; typedef long long ll; ll p,a; int whether(int p) { ; ;i*i<=p;i++) ) {…
1. poj 1995  Raising Modulo Numbers 2.链接:http://poj.org/problem?id=1995 3.总结:今天七夕,来发水题纪念一下...入ACM这个坑也快一年了 题意:求ai^bi和模m.裸快速幂 #include<iostream> #include<cstring> #include<cmath> #include<queue> #include<algorithm> #include<…