• Destroy the Moon to Save the Earth
  • Dijkstractions
  • Go Boards
  • Wuymul Wixcha
  • Edid Tistance
  • Travel Planning
  • A Giveaway
  • Game of XOR
  • National Bomb Defusing Squad
  • Rational Grading
  • Balanced String
  • Number of Connected Components
  • Extreme XOR Sum
  • Harmonic Matrix
  • In the Kingdom of Hirak
  • Prime Distance
  • 8-ball Rack
  • Within Arm’s Reach
  • Bribing Eve
  • Candle Box
  • Dinner Bet
  • Passwords
  • Performance Review
  • Cairo Corridor
  • Pascal’s Hyper-Pyramids
  • The White Rabbit Pocket Watch Alice: How can it be?
  • Risky Lottery
  • Balls and Needles
  • Verbal arithmetic
  • Pixel Art
  • The music teacher
  • Secret Santa
  • The entertainment of machines
  • Children to the top
  • Chocolate with almonds
  • Orchestral scores
  • Is it multiple of 3?
  • Smarter than hunger
  • The countess’ pearls
  • Sleeping in hostels
  • Tobby’s Ancestors
  • Tobby and Array
  • Counting Edges and Graphs
  • DPA Numbers I
  • Tobby and the quaseEquals strings
  • Felipe and the Sequence
  • Rectangular Sum
  • Humbertov and the Triangular Spiral
  • Rockabye Tobby
  • Tobby Primes
  • Tobby and the Skeletons
  • Rotations
  • DPA Numbers II
  • Logical Equivalence
  • Solve this Equation
  • Cuberoot This
  • Knight on Wide Board
  • Circles in Ellipse
  • Super Gifts
  • Sparse Domino Tiling
  • Firefighting Heroes
  • Disk Madness
  • Count these Permutations
  • Antivirus
  • Beautiful Triad
  • AirCraft: Monster
  • Drought In Nlogonia
  • My Password is a Palindromic Prime Number
  • Macarons in La Fête
  • Geonosis
  • How many inversions?
  • Quidditch Match
  • The Robot’s Grid
  • Polygonal Park
  • Problem with a ridiculously long name but with a ridiculously short description
  • Amazing Function The function F(n) is defined as:
  • Broken Calculator Keys
  • Cats and Vets
  • Delicious Binary Strings
  • Elegant Pillars
  • Faster Networks
  • Graph Colorings
  • Hobbit’s Resistor Graphs
  • Incredible Sums
  • Just Pentagon Perimeter
  • Katrina’s Shadow
  • Laser Avoidance
  • Alice’s Travels
  • Brackets Everywhere
  • Catch the Rats
  • Do Pillars Again
  • Easy Permutation Problem
  • Fantastic Sorting Algorithm
  • Graph Cut of Maximum XOR Weight
  • Hedgehogs Communicate
  • Intersecting Semi-Circles
  • Just More Permutations
  • Kid’s Simple Puzzle Problem
  • Looking at Divisors
  • Blade Ranas 2040
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