2017-03-28 Educational Codeforces #18: C. Divide by Three http://codeforces.com/contest/792/problem/C 続きを読む
2017-03-28 Educational Codeforces #18: E. Colored Balls http://codeforces.com/contest/792/problem/E 続きを読む
2017-03-16 Codeforces #404 E. Anton and Permutation http://codeforces.com/contest/785/problem/E 続きを読む