摘要：
链接：https://www.nowcoder.com/acm/contest/147/A来源：牛客网 Niuniu has recently learned how to use Gaussian elimination to solve systems of linear equations. 阅读全文
摘要：
链接：https://www.nowcoder.com/acm/contest/147/D来源：牛客网 Niuniu likes traveling. Now he will travel on a special graph. Given k and n, The directed graph c 阅读全文