欢迎访问我的新博客:http://www.milkcu.com/blog/ 原文地址:http://www.milkcu.com/blog/archives/1371281760.html 原创:[欧拉计划4]Largest palindrome product 摘要:找出两个3位数乘积得到的最大回文数 作者:MilkCu 题目描述 Problem 4 Largest palindrome product A palindromic number reads the same both way…
The prime factors of 13195 are 5, 7, 13 and 29. What is the largest prime factor of the number 600851475143 ? 翻译过后如下: 找出一个合数的最大质数因子 13195的质数因子有5,7,13和29. 600851475143的最大质数因子是多少? 做出答案以后的题解: 对于给定的n, 使factor = 2, 3, 4, 5, 6..., 对于每个factor, 当factor能被n完全整…
[题目一]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. [翻译]10以下的自然数中,属于3和5的倍数的有3,5,6和9,它们之和是23. 找出1000以下的自然数中,属于3和5…
先做个说明,里面所有的题都是我自己写的解题报告,由于我的能力有限,是个刚学java的小白,有很多不足的地方,还望各位大佬不奢赐教,谢谢! Largest product in a grid In the 20×20 grid below, four numbers along a diagonal line have been marked in red. 08 02 22 97 38 15 00 40 00 75 04 05 07 78 52 12 50 77 91 08 …
1 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. answer = sum $ takeWhile (< 1000) [ n | n <- [ 1 .. 999 ], mo…
问题重述: 2520 is the smallest number that can be divided by each of the numbers from 1 to 10 without any remainder. What is the smallest positive number that is evenly divisible by all of the numbers from 1 to 20? 问题的意思是找出可以整除小于等于某个数的所有公倍数,给出的测试用例是可以整除小…
那天的题挺简单的 下面来看下 No1 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. //project euler num1 #include <stdio.h> #inc…
A palindromic number reads the same both ways. The largest palindrome made from the product of two 2-digit numbers is 9009 = 91 99. Find the largest palindrome made from the product of two 3-digit numbers. def depart(n): DList = [] while n >= 10 : DL…
In an attempt to make peace with the Mischievious Mess Makers, Bessie and Farmer John are planning to plant some flower gardens to complement the lush, grassy fields of Bovinia. As any good horticulturist knows, each garden they plant must have the e…
题意:给定整数N,求1<=x,y<=N且Gcd(x,y)为素数的数对(x,y)有多少对 1<=N<=10^7 思路:莫比乌斯反演,同BZOJ2820…… ; ..max]of int64; prime,flag,f,mu:..max]of longint; n,m,i,j,t,v,cas:longint; function clac(n:longint):int64; var x,i,pos:longint; begin clac:=; i:=; while i<=n do…
大数据用 python? 速度感人 突然来了一发 python 欧拉筛,调了半天之后输入 1e7 过了几秒钟之后出解了,PY 果然神速 没学过 PY 的小同学可以当做 VB 的阅读程序,反正语言隔离都差不多[雾 Code import os import ssl import urllib import time import re import urllib def getPrime(n): v=[0 for i in range(n+3)] p=[] for i in range(2,n+1…
欧拉函数是积性函数——若m,n互质,φ(mn)=φ(m)φ(n). 特殊性质:当n为奇数时,φ(2n)=φ(n), φ(x)=x(1-1/p1)(1-1/p2)(1-1/p3)(1-1/p4)…..(1-1/pn), 其中p1,p2,p3,p4,……pn为x的所有质因数, 原因:如果x = p^k,那么p的所有倍数与x都不互质,所以除了p的倍数外的数的个数就是x*(1-1/p)个 比如下面的题目: Description Given n, a positive integer, how ma…