摘要：
Everybody knows any number can be combined by the prime number. Now, your task is telling me what position of the largest prime factor. The position o 阅读全文
摘要：
The least common multiple (LCM) of a set of positive integers is the smallest positive integer which is divisible by all the numbers in the set. For e 阅读全文
摘要：
A Compiler Mystery: We are given a C-language style for loop of type for (variable = A; variable != B; variable += C) statement; I.e., a loop which st 阅读全文
摘要：
Everybody in the Prime Land is using a prime base number system. In this system, each positive integer x is represented as follows: Let {pi}i=0,1,2,.. 阅读全文
摘要：
Given a sequence of consecutive integers n,n+1,n+2,...,m, an anti-prime sequence is a rearrangement of these integers so that each adjacent pair of in 阅读全文
摘要：
A prime number is a counting number (1, 2, 3, ...) that is evenly divisible only by 1 and itself. In this problem you are to write a program that will 阅读全文
摘要：
In 1742, Christian Goldbach, a German amateur mathematician, sent a letter to Leonhard Euler in which he made the following conjecture: Every even num 阅读全文
摘要：
For any even number n greater than or equal to 4, there exists at least one pair of prime numbers p1 and p2 such that n = p1 + p2 This conjecture has 阅读全文
摘要：
The sequence of n − 1 consecutive composite numbers (positive integers that are not prime and not equal to 1) lying between two successive prime numbe 阅读全文
摘要：
We say that x is a perfect square if, for some integer b, x = b 2. Similarly, x is a perfect cube if, for some integer b, x = b 3. More generally, x i 阅读全文
摘要：
Ms. Iyo Kiffa-Australis has a balance and only two kinds of weights to measure a dose of medicine. For example, to measure 200mg of aspirin using 300m 阅读全文
摘要：
Two positive integers are said to be relatively prime to each other if the Great Common Divisor (GCD) is 1. For instance, 1, 3, 5, 7, 9...are all rela 阅读全文
摘要：
Description 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 阅读全文
摘要：
Description A game-board consists of N fields placed around a circle. Fields are successively numbered from1 to N clockwise. In some fields there may 阅读全文
摘要：
In one well-known algorithm of finding the k-th order statistics we should divide all elements into groups of five consecutive elements and find the m 阅读全文
摘要：
Petya and Gena love playing table tennis. A single match is played according to the following rules: a match consists of multiple sets, each set consi 阅读全文
摘要：
ATMs of a well-known bank of a small country are arranged so that they can not give any amount of money requested by the user. Due to the limited size 阅读全文
摘要：
Simon has an array a1, a2, ..., an, consisting of n positive integers. Today Simon asked you to find a pair of integers l, r (1 ≤ l ≤ r ≤ n), such tha 阅读全文
摘要：
We all know the impressive story of Robin Hood. Robin Hood uses his archery skills and his wits to steal the money from rich, and return it to the poo 阅读全文
摘要：
Alice thinks an integer x is a K-wolf number, if every K adjacent digits in decimal representation of x is pairwised different. Given (L,R,K), please 阅读全文