Dirichlet's Theorem on Arithmetic Progressions Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 15398   Accepted: 7714 Description If a and d are relatively prime positive integers, the arithmetic sequence beginning with a and increasing…

Dirichlet's Theorem on Arithmetic Progressions Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 16733   Accepted: 8427 Description If a and d are relatively prime positive integers, the arithmetic sequence beginning with a and increasing…

poj3006 Dirichlet's Theorem on Arithmetic Progressions 很显然这是一题有关于素数的题目. 注意数据的范围,爆搜超时无误. 这里要用到筛选法求素数. 筛选法求素数的大概思路是: 如果a这个数是一个质数,则n*a不是质数.(年轻的孩子们不要纠结于判断a是否为素数) 用一个数组实现就是: memset(prime,true,sizeof(prime)); if (prime[i]) prime[i*j]=false; 部分程序如下: const m…

Dirichlet's Theorem on Arithmetic Progressions Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 13636   Accepted: 6808 Description If a and d are relatively prime positive integers, the arithmetic sequence beginning with a and increasing…

https://en.wikipedia.org/wiki/Fundamental_theorem_of_arithmetic In number theory, the fundamental theorem of arithmetic, also called the unique factorization theorem or the unique-prime-factorization theorem, states that every integer greater than 1[…

题目地址:http://poj.org/problem?id=3006 刷了好多水题,来找回状态...... Dirichlet's Theorem on Arithmetic Progressions Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 16803   Accepted: 8474 Description If a and d are relatively prime positive integers, t…

Time Limit:1000MS     Memory Limit:65536KB     64bit IO Format:%I64d & %I64u Submit cid=1006#status//I/0" class="ui-button ui-widget ui-state-default ui-corner-all ui-button-text-only" style="font-family:Verdana,Arial,sans-serif; f…

http://poj.org/problem?id=3006 #include <cstdio> using namespace std; bool pm[1000002]; bool usd[1000002]; bool judge(int x) { if(usd[x])return pm[x]; usd[x] = true; if(x == 2) return pm[x] = true; if(((x & 1) == 0) || (x < 2))return pm[x] =…

题目大意:a和d是两个互质的数,则序列a,a+d,a+2d,a+3d,a+4d ...... a+nd 中有无穷多个素数,给出a和d,找出序列中的第n个素数 #include <cstdio> int isPrime(int n) { || (n != && n % == )) ; ; i*i <= n; ++i) ) ; ; } int main() { int a,d,n,cun,temp; while(scanf("%d %d %d",&…

题目大意:给出一个等差数列,问这个等差数列的第n个素数是什么. 思路:这题主要考怎样筛素数,线性筛.详见代码. CODE: #include <cstdio> #include <cstring> #include <iostream> #include <algorithm> #define MAX 1000010 using namespace std; int prime[MAX],primes; bool notp[MAX]; int a,d,n;…

简单的暴力筛法就可. #include <iostream> #include <cstring> #include <cmath> #include <cctype> #include <cstdio> #include <cmath> #include <algorithm> #include <numeric> using namespace std; , M = ; bool is[N]; int pr…

题意 给出a d n    给出数列 a,a+d,a+2d,a+3d......a+kd 问第n个数是几 保证答案不溢出 直接线性筛模拟即可 #include<cstdio> #include<cstring> using namespace std; ]; ]; ]; int cnt; void Prime(int n){ cnt=; memset(Is_Primes,,sizeof(Is_Primes)); ;i<=n;i++){ if(!Is_Primes[i]) Pr…

题意: 设一个等差数列,首元素为a,公差为d 现在要求输入a,d,n ,要求找出属于该等差数列中的第n个素数并输出 思路:空间换时间是个主旋律.素数表的生成用素数筛选法.方法是从2开始,对每个目前还标记为素数的数(初始情况下每个数都标记为素数),把它的所有倍数都标记为非素数.这些扫描过去后,一直没被标记的(即保持为素数的)就是所有的素数. 之后的事情就比较简单了,对等差序列中的每个数一个个去查预先生成的素数表,一直数到第n个素数输出即可. #include <iostream> #includ…

http://poj.org/problem?id=3006 #include<stdio.h> #include<math.h> int is_prime(int n) { int i,m; ) ; m = sqrt(n); ; i <= m; i ++) { ) ; } ; } int main() { int a,d,n,i; while(~scanf("%d%d%d",&a,&d,&n)) { ; &&d==…

The Hundred Greatest Theorems The millenium seemed to spur a lot of people to compile "Top 100" or "Best 100" lists of many things, including movies (by the American Film Institute) and books (by the Modern Library). Mathematicians wer…

8-18-小练 A.HDU 1172   猜数字 采用枚举~[赤果果的暴力~] 代码: #include <iostream> #include <cstdio> #include <cstring> using namespace std; ],y[],s,ss,vis[],dis[]; ][]; void find(int b,int c) { ]-]) { s++;vis[]=; return; } ]-]) { s++;vis[]=; return; } ]-]…

FTA - 维基百科,自由的百科全书 FTA 维基百科,自由的百科全书   跳转至: 导航. 搜索 FTA可以指: 自由贸易协定(Free Trade Agreement) 自由贸易区(Free Trade Area) 美国联邦交通管理局(Federal Transit Administration) 故障树分析法(Fault Tree Analysis),即在系统设计过程中,通过对可能造成系统故障的各种因素(包括硬件.软件.环境.人为因素等)进行分析,画出逻辑框图(即故障树),从而确定系统故障…

                                                                             Dirichlet's Theorem on Arithmetic Progressions Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 15245   Accepted: 7641 Description If a and d are relatively prim…

I Proofs1 What is a Proof?2 The Well Ordering Principle3 Logical Formulas4 Mathematical Data Types5 Induction6 State Machines7 Recursive Data Types8 Infinite SetsII Structures9 Number Theory10 Directed graphs & Partial Orders11 Communication Networks…

A prime number p≥2 is an integer which is evenly divisible by only two integers: 1 and p. A composite integer is one which is not prime. The fundamental theorem of arithmetic says that any integer x can be expressed uniquely as a set of prime factors…

2992.357000 1000 A+B Problem1214.840000 1002 487-32791070.603000 1004 Financial Management880.192000 1003 Hangover792.762000 1001 Exponentiation752.486000 1006 Biorhythms705.902000 1005 I Think I Need a Houseboat686.540000 1011 Sticks647.566000 1007…

1. POJ 3299 Humidex 链接: http://poj.org/problem?id=3299 这道题是已知H,D,T三者的运算关系,然后告诉你其中两个.求另一个. #include<iostream> #include<cstdio> #include<cstring> #include<cmath> using namespace std; int main () { char c,h; double T,D,H; while(cin>…

本题有两个难点: 1 大量的数据输入.没处理好就超时 - 这里使用buffer解决 2 因子分解的算法 a)暴力法超时 b)使用sieve(筛子),只是当中的算法逻辑也挺不easy搞对的. 数值N因子分解逻辑: 1 保存全部能够sqrt(N)范围内的质素 2 找到能够被N除尽的质素d, 然后用d去除N.使用deg变量,保存度.即有多少个d能够被N除尽 3 用d去乘全部已经找到的因子(包含1),假设度deg大于1.那么循环i从1到deg, 用d*i去乘全部找到的因子 找到全部因子相加,减去N,就是…

质数(prime number)又称素数,有无限个.一个大于1的自然数,除了1和它本身外,不能被其他自然数整除,换句话说就是该数除了1和它本身以外不再有其他的因数:否则称为合数.      最小的质数是2. [例1]Goldbach's Conjecture (POJ 2262) Description In 1742, Christian Goldbach, a German amateur mathematician, sent a letter to Leonhard Euler in w…

Arithmetic operations taught in elementary schools are continuous in the high level topological point of view. This signifies that there is literally no clear boundary between simple and complex, low and high concepts. Instead, they both play indispe…

1 Introduction Modular arithmetic is a fundamental tool in modern algebra systems. In conjunction with the Chinese remainder theorem it serves as the workhorse in several algorithms computing the gcd, resultant etc. Moreover, it can serve as a very e…

ProofsSuppose first that $p$ is composite. Then $p$ has a factor $d > 1$ that is less than or equal to $p-1$. Then $d$ divides $(p-1)!$, so $d$ does not divide $(p-1)! + 1$. Therefore $p$ does not divide $(p-1)! + 1$. Two proofs of the converse are p…

Source: wiki: Parseval's theorem As for signal processing, the power within certain frequency band = the sum of (power spectrum at all frequencies within the frequency band)^2.…

A sequence of numbers is called arithmetic if it consists of at least three elements and if the difference between any two consecutive elements is the same. For example, these are arithmetic sequences: 1, 3, 5, 7, 9 7, 7, 7, 7 3, -1, -5, -9 The follo…

A sequence of number is called arithmetic if it consists of at least three elements and if the difference between any two consecutive elements is the same. For example, these are arithmetic sequence: 1, 3, 5, 7, 9 7, 7, 7, 7 3, -1, -5, -9 The followi…