ZOJ 3483 Gaussian Prime(数学啊 )
来源:互联网 发布:在线教育直播平台源码 编辑:程序博客网 时间:2024/04/28 08:27
题目链接:http://acm.zju.edu.cn/onlinejudge/showProblem.do?problemId=4280
In number theory, a Gaussian integer is a complex number whose real and imaginary part are both integers. The Gaussian integers, with ordinary addition and multiplication of complex numbers, form an integral domain, usually written as Z[i]. The prime elements of Z[i] are also known as Gaussian primes. Gaussian integers can be uniquely factored in terms of Gaussian primes up to powers of i and rearrangements.
A Gaussian integer a + bi is a Gaussian prime if and only if either:
- One of a, b is zero and the other is a prime number of the form 4n + 3 (with n a nonnegative integer) or its negative -(4n + 3), or
- Both are nonzero and a2 + b2 is a prime number (which will not be of the form 4n + 3).
0 is not Gaussian prime. 1, -1, i, and -i are the units of Z[i], but not Gaussian primes. 3, 7, 11, ... are both primes and Gaussian primes. 2 is prime, but is not Gaussian prime, as 2 = i(1-i)2.
Your task is to calculate the density of Gaussian primes in the complex plane [x1, x2] × [y1, y2]. The density is defined as the number of Gaussian primes divided by the number of Gaussian integers.
Input
There are multiple test cases. The first line of input is an integer T ≈ 100 indicating the number of test cases.
Each test case consists of a line containing 4 integers -100 ≤ x1 ≤ x2 ≤ 100, -100 ≤ y1 ≤ y2 ≤ 100.
Output
For each test case, output the answer as an irreducible fraction.
Sample Input
30 0 0 00 0 0 100 3 0 3
Sample Output
0/12/117/16
References
- http://en.wikipedia.org/wiki/Gaussian_integer
- Weisstein, Eric W. "Gaussian Prime." From MathWorld--A Wolfram Web Resource. http://mathworld.wolfram.com/GaussianPrime.html
代码如下:
//#pragma warning (disable:4786)#include <cstdio>#include <cmath>#include <cstring>#include <string>#include <cstdlib>#include <climits>#include <ctype.h>#include <queue>#include <stack>#include <vector>#include <utility>#include <deque>#include <set>#include <map>#include <iostream>#include <algorithm>using namespace std;const double eps = 1e-9;//const double pi = atan(1.0)*4;const double pi = 3.1415926535897932384626;const double e = exp(1.0);#define INF 0x3f3f3f3f//#define INF 1e18//typedef long long LL;//typedef __int64 LL;#define ONLINE_JUDGE#ifndef ONLINE_JUDGEfreopen("in.txt", "r", stdin);freopen("out.txt", "w", stdout);#endif#define maxn 100000int prim[maxn];void init(){ for(int i = 2; i <= maxn; i++) { if(!prim[i]) { for(int j = i+i; j <= maxn; j+=i) { prim[j] = 1; } } }}int GCD(int a, int b){ if(b == 0) return a; return GCD(b,a%b);}int main(){ int t; init(); scanf("%d",&t); int x1, x2, y1, y2; while(t--) { cin>>x1>>x2>>y1>>y2; int ans = 0; int tem; for(int x = x1; x <= x2; x++) { for(int y = y1; y <= y2; y++) { if(x == 0) { if(y < 0) { tem = -y; } else tem = y; if((tem-3)%4==0 && prim[tem]==0) ans++; } else if(y == 0) { if(x < 0) { tem = -x; } else tem = x; if((tem-3)%4==0 && prim[tem]==0) ans++; } else { tem = x*x+y*y; if(prim[tem]==0 && (tem-3)%4!=0) ans++; } } } int tol = (x2-x1+1)*(y2-y1+1); int gcd = GCD(ans,tol); printf("%d/%d\n",ans/gcd,tol/gcd); } return 0;}
- ZOJ 3483 Gaussian Prime(数学啊 )
- ZOJ 3483 Gaussian Prime
- ZOJ 3483 Gaussian Prime
- zoj - 2723 - Semi-Prime
- ZOJ 2723 Semi-Prime
- ZOJ 2723 Semi-Prime
- zoj 1312 Prime Cuts
- ZOJ 3911 Prime Query
- ZOJ 3911Prime Query
- ZOJ 3911 Prime Query
- Prime Query【ZOJ--3911】
- ZOJ 2723 Semi-Prime
- Prime Set ZOJ
- 数学: HDUCo-prime
- zoj 3041 City Selection(数学啊)
- ZOJ 3180 Number Game(数学啊 )
- ZOJ 3488 Conic Section(数学啊 )
- ZOJ 3327 Friend Number(数学啊 )
- 详谈双向链表的实现与简单操作
- Mac系统下安装ant
- recover-quack-data-structure
- 关于58车库网的介绍
- uva 10405 LCS + 空格卡wa
- ZOJ 3483 Gaussian Prime(数学啊 )
- MQTT协议笔记之-连接和心跳
- delphi5安装教程
- 计算机网络基础笔记1
- HDOJ 1532 Drainage Ditches
- Eclipse里面的快捷键小记
- 【ok】获取文件夹下所有文件(包括文件夹)
- 状态模式
- 杭电 HDU ACM 1334 Perfect Cubes