Hello everyone!
I invite you to participate in the upcoming short contest at CodeChef.com (http://www.codechef.com/COOK16). The contest starts on November 20 at 20:00 Moscow time (check the starting time in other time zones here). This time I'm setting the problems, while Anton Lunyov () is the tester. Anton made a significant contribution into setting the contest, so my big "thank you" goes to him :)
Here is some information for those who has never participated in short contests at CodeChef. The length of the contest is 2.5 hours, there will be 5 problems of different difficulty levels. The contest will be held by the traditional ACM rules. No special registration for the contest is needed, it's enough to register at the CodeChef site.
Unfortunately I won't be able to monitor the contest as I'll participate in All-Russian School Team Olympiad in Programming on the same day. Nevertheless, Anton will be able to answer all your questions (if any).
Good luck! ;)
I invite you to participate in the upcoming short contest at CodeChef.com (http://www.codechef.com/COOK16). The contest starts on November 20 at 20:00 Moscow time (check the starting time in other time zones here). This time I'm setting the problems, while Anton Lunyov () is the tester. Anton made a significant contribution into setting the contest, so my big "thank you" goes to him :)
Here is some information for those who has never participated in short contests at CodeChef. The length of the contest is 2.5 hours, there will be 5 problems of different difficulty levels. The contest will be held by the traditional ACM rules. No special registration for the contest is needed, it's enough to register at the CodeChef site.
Unfortunately I won't be able to monitor the contest as I'll participate in All-Russian School Team Olympiad in Programming on the same day. Nevertheless, Anton will be able to answer all your questions (if any).
Good luck! ;)
Contest discussion
Problem A. Noldbach problem
To solve this problem you were to find prime numbers in range [2..N]. The constraints were pretty small, so you could do that in any way - using the Sieve of Eratosthenes or simply looping over all possible divisors of a number.
Take every pair of neighboring prime numbers and check if their sum increased by 1 is a prime number too. Count the number of these pairs, compare it to K and output the result.
Problem B. Hierarchy
Problem A. Noldbach problem
To solve this problem you were to find prime numbers in range [2..N]. The constraints were pretty small, so you could do that in any way - using the Sieve of Eratosthenes or simply looping over all possible divisors of a number.
Take every pair of neighboring prime numbers and check if their sum increased by 1 is a prime number too. Count the number of these pairs, compare it to K and output the result.
Problem B. Hierarchy