Codeforces Beta Round 85 (Div. 1 Only) B. Petya and Divisors
Codeforces Beta Round 89 (Div. 2) C. Fancy Number
Codeforces Beta Round 90 B. Before Exam
Chocolates
Bob and the apples
Highways
Path queries
Infinite K-tree
School Regional Team Contest, Saratov, 2011 J. Minimum Sum
Codeforces Beta Round 91 (Div. 1 Only) C. Lucky Permutation