Sherlock and Array
Beautiful Pairs
Weighted Uniform Strings
Extremum Permutations
Educational Codeforces Round 32 E. Maximum Subsequence
Codeforces Round 447 (Div. 2) B. Ralph And His Magic Field
Codeforces Round 452 (Div. 2) D. Shovel Sale
Codeforces Round 455 (Div. 2) C. Python Indentation
Educational Codeforces Round 35 (Rated for Div. 2) D. Inversion Counting
Dominoes Rotations