【Educational Codeforces Round 49 (Rated for Div. 2) 】 A:https://www.cnblogs.com/myx12345/p/9843826.html B:https://www.cnblogs.com/myx12345/p/9843869.html C:https://www.cnblogs.com/myx12345/p/9843918.html D: E: F: G: