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…

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…

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…

模板题,直接用 /********************* Template ************************/ #include <set> #include <map> #include <list> #include <cmath> #include <ctime> #include <deque> #include <queue> #include <stack> #include &…

题目链接 题意:题目定义了Carmichael Numbers 即 a^p % p = a.并且p不是素数.之后输入p,a问p是否为Carmichael Numbers? 坑点:先是各种RE,因为poj不能用srand()...之后各种WA..因为里面(a,p) ?= 1不一定互素,即这时Fermat定理的性质并不能直接用欧拉定理来判定..即 a^(p-1)%p = 1判断是错误的..作的 #include<iostream> #include<cstdio> #include&l…

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…

GCD & LCM Inverse Time Limit: 2000MS Memory Limit: 65536K Total Submissions: 9756Accepted: 1819 Description Given two positive integers a and b, we can easily calculate the greatest common divisor (GCD) and the least common multiple (LCM) of a and b.…

Prime Test Time Limit: 6000MS Memory Limit: 65536K Total Submissions: 29193 Accepted: 7392 Case Time Limit: 4000MS Description Given a big integer number, you are required to find out whether it's a prime number. Input The first line contains the num…

Prime Test Time Limit: 6000MS Memory Limit: 65536K Total Submissions: 29193 Accepted: 7392 Case Time Limit: 4000MS Description Given a big integer number, you are required to find out whether it's a prime number. Input The first line contains the num…

一些前置知识可以看一下我的联赛前数学知识 如何判断一个数是否为质数 方法一:试除法 扫描\(2\sim \sqrt{n}\)之间的所有整数,依次检查它们能否整除\(n\),若都不能整除,则\(n\)是质数,否则\(n\)是合数. 代码 bool is_prime(int n){ if(n<2) return 0; int m=sqrt(n); for(int i=2;i<=m;i++){ if(n%i==0) return 0; } return 1; } 方法二.线性筛 用 \(O(n)\)…