Cute problems

• 2136E - By the Assignment
• 2096D - Wonderful Lightbulbs
• 2130E2 - Interactive RBS (Medium Version)

Smashable problems

• 2154D - Catshock
• 2156D - Find the Last Number
• 2180C - XOR-factorization (ok this ones controversial but give it some love cmon)
• 2109D - D/D/D