Math
Problems on math, including arithmetic and algebra, sequences and series, divisibility and remainders, equations and inequalities, long arithmetic, matrices and linear algebra, numeral systems, and formulas that replace a slow simulation.
Narrower problem sets are under Number theory, Combinatorics, Geometry, Probabilities and Matrix.
Problems
Simple problem#1
Very easy
Gardener#10
Easy
Dragon#16
Medium
New-year tree#23
Medium
Product#28
Medium
The Cost of the K-dominoes#51
Very easy
The Billiards#58
Very easy
Cleaning up the Snow#61
Very easy
The Factorial#62
Easy
Mytsyk and the flowers#63
Very easy
Cheese for Anfisa - 2#67
Very easy
The Expression from the Numbers#71
Very easy
Bell numbers#97
Very easy
Lines#99
Hard
Page Numbering#109
Very easy
Clocks#111
Easy
Cake#112
Very easy
Long number#116
Easy
Raft#117
Very easy