摘要： Matrix Power SeriesTime Limit: 3000MSMemory Limit: 131072KTotal Submissions: 8632Accepted: 3697DescriptionGiven a n × n matrix A and a positive integer k, find the sum S = A + A2 + A3 + … + Ak.InputThe input contains exactly one test case. The first line of input contains three positive integer 阅读全文

摘要： Mersenne Composite NumbersTime Limit: 1000MSMemory Limit: 65536KTotal Submissions: 1494Accepted: 698DescriptionOne of the world-wide cooperative computing tasks is the "Grand Internet Mersenne Prime Search" -- GIMPS -- striving to find ever-larger prime numbers by examining a particular ca 阅读全文

摘要： DiscountTime Limit: 2000/1000 MS (Java/Others)Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 57Accepted Submission(s): 47Problem DescriptionAll the shops use discount to attract customers, but some shops doesn’t give direct discount on their goods, instead, they give discount only whe 阅读全文

摘要： Pseudoprime numbersTime Limit: 1000MSMemory Limit: 65536KTotal Submissions: 4496Accepted: 1716DescriptionFermat's theorem states that for any prime number p and for any integer a > 1, ap = a (mod p). That is, if we raise a to the pth power and divide by p, the remainder is a. Some (but not ve 阅读全文

摘要： POJ 3126, Prime PathTime Limit: 1000MSMemory Limit: 65536KTotal Submissions: 3134Accepted: 1911DescriptionThe ministers of the cabinet were quite upset by the message from the Chief of Security stating that they would all have to change the four-digit room numbers on their offices. — It is a matter 阅读全文

摘要： Prime GapTime Limit: 5000MSMemory Limit: 65536KTotal Submissions: 6070Accepted: 3454DescriptionThe sequence of n − 1 consecutive composite numbers (positive integers that are not prime and not equal to 1) lying between two successive prime numbers p and p + n is called a prime gap of length n. For e 阅读全文

摘要： Sum of Consecutive Prime NumbersTime Limit: 1000MSMemory Limit: 65536KTotal Submissions: 12073Accepted: 6767DescriptionSome positive integers can be represented by a sum of one or more consecutive prime numbers. How many such representations does a given positive integer have? For example, the integ 阅读全文

摘要： CARDSTime Limit: 1000MSMemory Limit: 10000KTotal Submissions: 872Accepted: 437DescriptionAlice and Bob have a set of N cards labelled with numbers 1 ... N (so that no two cards have the same label) and a shuffle machine. We assume that N is an odd integer. The shuffle machine accepts the set of card 阅读全文

摘要： CipherTime Limit: 1000MSMemory Limit: 10000KTotal Submissions: 15186Accepted: 3897DescriptionBob and Alice started to use a brand-new encoding scheme. Surprisingly it is not a Public Key Cryptosystem, but their encoding and decoding is based on secret keys. They chose the secret key at their last me 阅读全文

摘要： Cow SortingTime Limit: 2000MSMemory Limit: 65536KTotal Submissions: 4110Accepted: 1459DescriptionFarmer John's N (1 ≤ N ≤ 10,000) cows are lined up to be milked in the evening. Each cow has a unique "grumpiness" level in the range 1...100,000. Since grumpy cows are more likely to damag 阅读全文