My algorithm problems

Below is the list of problems I invented for various programming competitions.

Polish Olympiad in Informatics

• Fibonacci representation (19th Polish Olympiad in Informatics, 2nd stage)
  Problem description (PL) Booklet with solution (PL)
• Bidding (19th Polish Olympiad in Informatics, finals)
  Problem description (PL) Booklet with solution (PL)
• Laser (20th Polish Olympiad in Informatics, finals)
  Problem description (PL) Booklet with solution (PL)
• Trips (22nd Polish Olympiad in Informatics, finals)
  Problem description (EN) Booklet with solution (PL)
• Beads (23rd Polish Olympiad in Informatics, 1st stage)
  Problem description (PL) Video solution (PL)
• Digit sum (24th Polish Olympiad in Informatics, 2nd stage)
  Problem description (PL)
• Fence (25th Polish Olympiad in Informatics, finals)
  Problem description (PL)
• Taxi (25th Polish Olympiad in Informatics, finals)
  Problem description (PL)
• Subsequences (26th Polish Olympiad in Informatics, 1st stage)
  Problem description (PL) Solution (PL)
• Game of divisors (26th Polish Olympiad in Informatics, finals)
  Problem description (EN)
• Least common multiple (27th Polish Olympiad in Informatics, 1st stage)
  Problem description (EN)
• Kindergarten (27th Polish Olympiad in Informatics, 1st stage)
  Problem description (EN)
• Nursery's difficult dillemma (27th Polish Olympiad in Informatics, 2nd stage)
  Problem description (PL)
• Knapsack packing (28th Polish Olympiad in Informatics, 2nd stage)
  Problem description (PL)
• Sum of primes (28th Polish Olympiad in Informatics, finals)
  Problem description (PL)
• Dominoes (29th Polish Olympiad in Informatics, 1st stage)
  Problem description (PL)
• Coprime numbers (29th Polish Olympiad in Informatics, 2nd stage)
  Problem description (PL)
• Meteors (29th Polish Olympiad in Informatics, finals)
  Problem description (PL)
• Scales (29th Polish Olympiad in Informatics, finals)
  Problem description (PL)
• Treasure (31st Polish Olympiad in Informatics, finals)
  Problem description (PL)

Polish Junior Olimpiad in Informatics

The following list is incomplete, I chose only few problems I find interesting.

• Even-digit Numbers (14th Polish Junior Olympiad in Informatics, 1st stage)
  Problem description (PL) Solution (PL) Video solution (PL)
• Number process (14th Polish Junior Olympiad in Informatics, 1st stage)
  Problem description (PL) Solution (PL) Video solution (PL)
• Unlucky numbers (14th Polish Junior Olympiad in Informatics, 1st stage)
  Problem description (PL) Solution (PL)
• Zigzag (14th Polish Junior Olympiad in Informatics, 2nd stage)
  Problem description (PL) Solution (PL) Video solution (PL)
• Speedrun (14th Polish Junior Olympiad in Informatics, 1st stage)
  Problem description (PL) Solution (PL) Video solution (PL)
• Fences (15th Polish Junior Olympiad in Informatics, 2nd stage)
  Problem description (PL) Video solution (PL)
• Multiplication (16th Polish Junior Olympiad in Informatics, 1st stage)
  Problem description (PL)
• Drawing triangles (16th Polish Junior Olympiad in Informatics, finals)
  Problem description (PL) Solution (PL)

Central European Olympiad in Informatics

• Cloud Computing (25th Central European Olympiad in Informatics)
  Problem description (EN)
• Toys (25th Central European Olympiad in Informatics)
  Problem description (EN)

Polish Collegiate Programming Contest

• Album of numbers (20th Polish Collegiate Programming Contest)
• Accurate shots (20th Polish Collegiate Programming Contest)
• Prom (20th Polish Collegiate Programming Contest)
• Pen (20th Polish Collegiate Programming Contest)
• Insects (20th Polish Collegiate Programming Contest)
• Blocks (20th Polish Collegiate Programming Contest)
• Postman (20th Polish Collegiate Programming Contest)

Problemset (EN) Presentation of solutions (PL) Video solutions (PL)

• Weak pseudorandom generator (21st Polish Collegiate Programming Contest)
• Generating polygons (21st Polish Collegiate Programming Contest)
• Grapes (21st Polish Collegiate Programming Contest)
• Taxi (21st Polish Collegiate Programming Contest)
• Parking Lot (21st Polish Collegiate Programming Contest)
• Anagrams (21st Polish Collegiate Programming Contest)
• Rock, paper, scissors (21st Polish Collegiate Programming Contest)

Problemset (EN) Presentation of solutions (PL)

• Alternative permutations (22nd Polish Collegiate Programming Contest)
• Identifier sequence (22nd Polish Collegiate Programming Contest)
• English (22nd Polish Collegiate Programming Contest)
• Encryption function (22nd Polish Collegiate Programming Contest)
• Printer's head (22nd Polish Collegiate Programming Contest)
• Laser intensification (22nd Polish Collegiate Programming Contest)
• Maximal Sandbox (22nd Polish Collegiate Programming Contest)

Problemset (EN) Presentation of solutions (PL)

• Fibonaccis' vouchers (23rd Polish Collegiate Programming Contest)
• Chinese remainder theorem (23rd Polish Collegiate Programming Contest)
• Baking pans (23rd Polish Collegiate Programming Contest)
• Taste in art (23rd Polish Collegiate Programming Contest)
• Hobby (23rd Polish Collegiate Programming Contest)
• Pocket money (23rd Polish Collegiate Programming Contest)
• Lines (23rd Polish Collegiate Programming Contest)

Problemset (EN) Presentation of solutions (PL)

Google Code Jam

• The Last Word (Round 1A, 2016)
  Problem description (EN)

Algorithmic Engagements

• Euler's Problem (Algorithmic Engagements 2013, finals)
  Problem description (EN)
• Word (Algorithmic Engagements 2016, test round)
  
• Polygonal chain (Algorithmic Engagements 2016, finals)
  Problem description (PL)

Marathon24

• Eurovision Song Contest (deepsense.io marathon24 Warsaw 2015, qualifications)