ZeroSnake0

摘要： The prime factors of 13195 are 5, 7, 13 and 29.What is the largest prime factor of the number 600851475143 ?首先将给定n不断除以2，然后可只考虑奇因子求出小于sqrt(n)的最大的n的奇因子，然后递归求解Python代码：from math import sqrtfrom math import truncfrom time import clocknb = 600851475143def g(n): """ n is odd ""&qu 阅读全文

摘要： Each new term in the Fibonacci sequence is generated by adding the previous two terms. By starting with 1 and 2, the first 10 terms will be:1, 2, 3, 5, 8, 13, 21, 34, 55, 89, ...By considering the terms in the Fibonacci sequence whose values do not exceed four million, find the sum of the even-value 阅读全文

摘要： If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9. The sum of these multiples is 23.Find the sum of all the multiples of 3 or 5 below 1000.对给定的max和k，小于max的k的倍数的个数为 c = (max - 1) / k值分别为 k, 2k, ... , ck,则总和为 k(1 + 2 + ... + c) = k(1+c)c/2Python代码：max = ... 阅读全文