题目链接https://www.nowcoder.com/acm/contest/145/C题目描述A binary string s of length $N = 2^n$ is given. You will perform the following operation n times :Choose one of the operators AND (&), OR (|) or XO...
题目链接http://codeforces.com/contest/987/problem/D题目Some company is going to hold a fair in Byteland. There are n towns in Byteland and m two-way roads between towns. Of course, you can reach any town...
题目链接http://codeforces.com/contest/984/problem/E题目You work in a big office. It is a $9$ floor building with an elevator that can accommodate up to $4$ people. It is your responsibility to manage thi...
题目链接：http://exam.upc.edu.cn/problem.php?id=5247题目：题目描述At some point or another, most computer science students have written a standard Sudoku solving program. This is yet another “put numbers in a...
题目链接：http://exam.upc.edu.cn/problem.php?id=5124题目：题目描述Flow Free is a puzzle that is played on a 2D grid of cells, with some cells marked as endpoints of certain colors and the rest of cells being b...