codeforces #323 div 2 B. Robot's Task(又是暴力？

C. GCD Table time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output The GCD table G of size n × n for an array of positive integers a of length n is defined by formula

D. Three Logos time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Three companies decided to order a billboard with pictures of their logos. A billboard is a big square board. A logo of each company is a rectangle of a non-zero area.