偶数除了二都不是素数 一个数 n 如果是合数,那么它的所有的因子不超过sqrt(n)--n的开方 int i, j, n = 10000; for (i = 3; i <= n; i += 2) { for (j = 2; j < (Math.Sqrt(i) + 1); j++) { if (i % j == 0) break; } if (j > Math.Sqrt(i)) Console.WriteLine("{0}", i); }…
四位玫瑰数 描述 四位玫瑰数是4位数的自幂数.自幂数是指一个 n 位数,它的每个位上的数字的 n 次幂之和等于它本身.…
本题来自 Project Euler 第21题:https://projecteuler.net/problem=21 ''' Project Euler: Problem 21: Amicable numbers Let d(n) be defined as the sum of proper divisors of n (numbers less than n which divide evenly into n). If d(a) = b and d(b) = a, where a ≠ b…
python求100以内素数之和 from math import sqrt # 使用isPrime函数 def isPrime(n): if n <= 1: return False for i in range(2, int(sqrt(n)) + 1): if n % i == 0: return False return True count = 0 for i in range(101): if isPrime(i): count += i print(count) # 单行程序扫描素数…
//函数fun功能:求n(n<10000)以内的所有四叶玫瑰数并逐个存放到result所指数组中,个数作为返回值.如果一个4位整数等于其各个位数字的4次方之和,则称该数为函数返回值. #include<stdio.h> #pragma warning (disable:4996) int fun(int n, int result[]) { ,j=; int a, b, c, d; ; i < n; i++) { a = i / ; b = (i % ) / ; c = (i %…
print 'Find prime number smaller then input number \n' print 'Please input a number:' import datetime begintime=datetime.datetime.now() number=raw_input() num=1 end=[] b=0 n=0 while num<int(number): div=1 while div<num: result=float(num)/div if floa…
The binomial coefficient C(m,n) is defined as Given four natural numbers p, q, r, and s, compute the the result of dividing C(p,q) by C(r,s). 这是二次项系数,现在给出p,q,r,s,计算C(p,q)除以C(r,s)的结果 InputInput consists of a sequence of lines. Each line contains four non…
"Problem: To print in ascending order all primes less than 10000. Use an array of processes, SIEVE, in which each process inputs a prime from its predecessor and prints it. The process then inputs an ascending stream of numbers from its predecessor a…
