摘要：``` include include include include using namespace std; const int eps=1E 8; typedef vector vec; typedef vector mat; //求解Ax=b，A是方阵 //当方程组无解或者有无穷多解时，返回 阅读全文

摘要：You have an array a with length n, you can perform operations. Each operation is like this: choose two adjacent elements from a, say x and y, and repl 阅读全文

摘要：You are given a multiset of n integers. You should select exactly k of them in a such way that the difference between any two of them is divisible by 阅读全文

摘要：You are given three n × n matrices A, B and C. Does the equation A × B = C hold true? You are given three n × n matrices A, B and C. Does the equation 阅读全文

摘要：A. Do you want a date? time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output A. Do you want a 阅读全文