Index Problem Difficulty Solved Comments 1 Hit the Lottery 800 2 Even Subset Sum Problem 800 3 Card Constructions 1100 4 Petr and a Combination Lock 1200 5 Cutting 1200 6 Creating the Contest 1200 7 Ternary String 1200 8 Restricted RPS 1200 9 Young Explorers 1200 10 Polygon 1300 11 Homecoming 1300 12 Just Eat It! 1300 13 Lose it! 1300 14 WOW Factor 1300 15 Candies! 1400 16 Basketball Exercise 1400 17 Three displays 1400 18 The Number of Products 1400 19 Orac and Models 1400 20 Skyscrapers (easy version) 1500 21 Gas Pipeline 1500 22 Two Arrays 1600 23 Standard Free2play 1600 24 Linova and Kingdom 1600 25 New Year and the Permutation Concatenation 1700 26 Magic Tricks 1700 27 Three Blocks Palindrome (easy version) 1700 28 Yet Another Monster Killing Problem 1700 29 Stars Drawing (Easy Edition) 1700 30 Maximum White Subtree 1800 31 Compression 1800 32 Garland 1800 33 K Balanced Teams 1800 34 Nauuo and Circle 1900 35 Pavel and Triangles 1900 36 Treasure Island 1900 37 K-periodic Garland 1900 38 White Lines 1900 39 Yet Another Subarray Problem 1900 40 Stars Drawing (Hard Edition) 1900 41 Array Without Local Maximums 1900 42 Classy Numbers 1900 43 A Game with Traps 1900 44 Skyscrapers (hard version) 1900 45 Vasya and Good Sequences 2000 46 Minimax Problem 2000 47 Three Paths on a Tree 2000 48 Sequence Sorting 2000 49 String Coloring (hard version) 2000 50 Yet Another Division Into Teams 2000 51 Sergey and Subway 2000 52 Lynyrd Skynyrd 2000 53 Rotate Columns (easy version) 2000 54 Roman Digits 2000 55 Cards and Joy 2000 56 Number of Components 2100 57 Pictures with Kittens (hard version) 2100 58 Lunar New Year and Red Envelopes 2100 59 Yet another 2D Walking 2100 60 You Are Given a WASD-string... 2100 61 Magic Gems 2100 62 Shovels Shop 2100 63 Inverse Coloring 2100 64 Mysterious Code 2100 65 Array Shrinking 2100 66 Rain and Umbrellas 2100 67 Common Number 2100 68 Xor-Paths 2100 69 Find a Number 2200 70 Three Pieces 2200 71 Addition on Segments 2200 72 Minimal Segment Cover 2200 73 Three Religions 2200 74 Makoto and a Blackboard 2200 75 Tourism 2200 76 Palindrome-less Arrays 2200 77 Rectangle Painting 1 2300 78 Discarding Game 2300 79 Sonya and Informatics 2300 80 Card Bag 2300 81 Steps to One 2300 82 String Multiplication 2300 83 Team Building 2300 84 Another Filling the Grid 2300 85 Nauuo and Pictures (easy version) 2300 86 Voting (Easy Version) 2300 87 Hyakugoku and Ladders 2300 88 Bracket Substring 2300 89 Culture Code 2300 90 Cookies 2400 91 Sonya and Ice Cream 2400 92 Balanced Binary Search Trees 2400 93 GCD Counting 2400 94 Vasya and Maximum Profit 2400 95 Vasya and Array 2400 96 Nastya and Unexpected Guest 2400 97 Economic Difficulties 2400 98 Vasya and Binary String 2400 99 Animal Observation (hard version) 2400 100 Split the Tree 2400