HXX904的博客

问题：When a radio station is broadcasting over a very large area, repeaters are used to retransmit the signal so that every receiver has a strong signal. However, the channels used by each repeater mu...

一个整数除以3余2，除以5余3，除以7余2，求这个整数。除以3余2和除以7余2的数可以写成21n+2。21n+2除以5余3，要求21n除以5余1。21n除以5余1，21除以5余1，要求n除以5余1（乘数之余等于余数之乘），则n最小取1。所以满足“除以3余2，除以5余3，除以7余2”的最小的数是21×1+2=23。标准解法：先从3和5、3和7、5和7的公倍数中相应地找出分别被7、5、3除均余1的较小数15、21、70 ( 注释:此步又称为求"模逆"运算,利用扩展欧几里得法并借助计算机编程可比较快速地

题目:今天是贝茜的生日，为了庆祝自己的生日，贝茜邀你来玩一个游戏。贝茜让 N 头奶牛坐成一个圈。除了 1 号与 N号奶牛外，i号奶牛与 i − 1 号和 i + 1号奶牛相邻，N 号奶牛与 1 号奶牛相邻。农夫约翰用很多纸条装满了一个桶，每一张包含了一个 1 到 10^6的数字。接着每一头奶牛 i 从桶中取出一张纸条 Ai，每头奶牛轮流走一圈，同时拍打所有编号能整除在纸条上的数字的牛的头，然后走回到原来的位置。奶牛们想让你帮他们计算，对于每头奶牛，它需要拍多少头奶牛的头？输入格式第一行包含...

题目：Sigma function is an interesting function in Number Theory. It is denoted by the Greek letterSigma (σ). This function actually denotes the sum of all divisors of a number. For example σ(24) = 1+2+3+4+6+8+12+24=60. Sigma of small numbers is easy to fi.

欧拉函数：欧拉函数是小于或等于n的正整数中与n互质的数的数目（因此φ(1)=1）求一个数的欧拉值为：欧拉降幂公式：

问题：Given an integern, you have to findlcm(1, 2, 3, ..., n)lcmmeans least common multiple. For example lcm(2, 5, 4) = 20, lcm(3, 9) = 9, lcm(6, 8, 12) = 24.InputInput starts with an integerT (≤ 10000), denoting the number of test cases.Each c...

问题：The football season has just ended in Berland. According to the rules of Berland football, each match is played between two teams. The result of each match is either a draw, or a victory of one o...

问题：Given two positive integers G and L, could you tell me how many solutions of (x, y, z) there are, satisfying that gcd(x, y, z) = G and lcm(x, y, z) = L?Note, gcd(x, y, z) means the greatest com...

问题：Given the value of N, you will have to find the value of G. The definition of G is given below: Here GCD(i, j) means the greatest com...

问题：两只青蛙在网上相识了，它们聊得很开心，于是觉得很有必要见一面。它们很高兴地发现它们住在同一条纬度线上，于是它们约定各自朝西跳，直到碰面为止。可是它们出发之前忘记了一件很重要的事情，既没有问清楚对方的特征，也没有约定见面的具体位置。不过青蛙们都是很乐观的，它们觉得只要一直朝着某个方向跳下去，总能碰到对方的。但是除非这两只青蛙在同一时间跳到同一点上，不然是永远都不可能碰面的。为了帮助这两只乐...

#include<stdio.h>#include<string.h>#include<math.h>#include<cmath>#include<cstdio>#include<cstring>#define N 10005#define X 1000000#define mem(a) memset(a,...

问题：As we all know, the next Olympic Games will be held in Beijing in 2008. So the year 2008 seems a little special somehow. You are looking forward to it, too, aren't you? Unfortunately there still ...

问题：In mathematics, thenthharmonic number is the sum of the reciprocals of the firstnnatural numbers: ...

问题：Dr. Mob has just discovered a Deathly Bacteria. He named it RC-01. RC-01 has a very strange reproduction system. RC-01 lives exactlyxdays. Now RC-01 produces exactlypnew deadly Bacteria where...

问题：Amakusa, the evil spiritual leader has captured the beautiful princess Nakururu. The reason behind this is he had a little problem with Hanzo Hattori, the best ninja and the love of Nakururu. Aft...

问题：Consider a positive integer X,and let S be the sum of all positive integer divisors of 2004^X. Your job is to determine S modulo 29 (the rest of the division of S by 29).Take X = 1 for an examp...

问题：You are given two integers:nandk, your task is to find the most significant three digits, and least significant three digits ofnk.InputInput starts with an integerT (≤ 1000), denoting th...