Lewin Gan

The January 2011 Cook-Off

Holes in the text

March Cook-off Challenge

Money Transformation

April Long Contest

Number Game Revisited, Rectangles Counting

May Long Contest 2011

Pruning Trees, Tree Product, The Great Wall of Byteland, Bickering Cooks

June Long Contest 2011

Maximal Score Path, Chef Teams

July 2011 Long Contest

Large Kitchen, A-E Hash Function, Most Popular Friend

August Long Contest 2011

Infinite Grid Game, Complex Spanning Tree

September Long Contest

Younger Brother, BIT Magazine

October Long Contest 2011

Dish Distribution

November Long Contest 2011

Chefs new Pet

December 2011 Long Contest

Birthday Gift, Robot Movings, Ciel and Eggs

January 2012 Challenge

Houses and Restaurants

February 2012 Challenge

Lucky Count, Lucky Long, Word Couting, Count of Maximum

March 2012 Challenge

Longest Weird Subsequence, Cosine Partition Function, Lucky Number, Free Shuttle Service, Home Delivery, Spoon in Matrix

April Challenge 2012

Lucky Array, Parallel Computing, Fit to Play, Double Strings, Stacking Pancakes, Greatest Dumpling Fight, Similar Graphs

May Challenge 2012

Digits Forest, Killing Gs, Little Elephant and Median, Jewels and Stones, Lucky lucky number, Divisible Pairs, Remember the recipe, A Home for Chef

May Cook-Off 2012

Little Elephant and Strings

June Challenge 2012

Little Elephant and Candies, Arranging Cup-cakes

July Challenge 2012

Chef's Dream, My Fair Coins, Gift Rift

August Challenge 2012

Little Elephant and Bombs, Lucky Driving, Range of Data, Delivery Boy

September Challenge 2012

Kisses & Hugs, Racing Horses, ChefTown Parade, Three is Crowd

October Challenge 2012

Little Elephant and Order, Fierce Battles, Event Organizer, The New Scheme, Need More Diamonds

November Challenge 2012

Coin Flip, Sridhar Likes Travelling

December Challenge 2012

Sereja and Data Structures , Granama Recipes, Book Exercises, Magic Rankings, The Uncountable Ways, Pizza Delivery

January Challenge 2013

Little Elephant and Alcohol, The Minimum Number Of Moves, End Of The World, Chef of the Year, Three Different Numbers

February 2013 Challenge

Little Elephant and Cards, Buy1-Get1, Climbing Stairs

March Challenge 2013

Random decreasing function, Tourist Translations, Approximately, Fire Escape Routes, Minesweeper

April Challenge 2013

Little Elephant and Music, Barcelona Gameplay Tactics, ChefGame, Kingdom Unity, Fault Tolerance, Maximum Weight Difference, Levy Conjecture, Cylinder

May Challenge 2013

Matchsticks, Witua and Math, Tree Counting, Password Cracking Challenge, Juno Puzzle for May, Name Reduction, Your Name is Mine, Field Trip

June Challenge 2013

Little Elephant and Mouses, Collecting Magical Berries, Just Some Permutations 3, Dessert Wizard, Two k-Convex Polygons, Predictopus, To challenge or not, W String, Lapindromes

May Cook-off 2013

Subtraction Game 1, Subtraction Game 2, Sequence Transmission

July Challenge 2013

Mountain Holidays, Galactik Football, The Probability Of Winning, Chef and Walking on the rectangle , Count K-Primes, Sereja and Sorting, Circle of death

August Challenge 2013

Little Elephant and Lemonade, Hello Hello, Save The Princess, The Number Of Solutions, Chef and Segments, Deleting numbers, Splitting Candies

September Challenge 2013

Little Elephant and Exams, Merciless Chef, Cool Guys, Chef and Integers , Project Spoon, CAO Stage-1, CAO Stage-2, Sereja and Snake

October Challenge 2013

Little Elephant and Bamboo, Helping Lira, Maxim and Dividers, Sereja and Transformation, CAO Stage-3, Yet Another Nice Girl, Edit Distance on Grid, Kamehameha

November Challenge 2013

Chef Game, Superpowers of 2, Yet Another Cute Girl, Sereja and Vectors, Uncle Johny, Square Digit Squares, Missing some chairs

December Challenge 2013

Lucy and the Flowers, Art in Digital Age, Cube Cakes, Chef and Codes, Funny Marbles, Magic Pairs, Reign, Rectangular Queries

January Challenge 2014

Magic Trick, Sereja and Graph, Counting D-sets, ForbiddenSum, Meteor, Byteland Tours, Bon Appetit, Please like me, Chef and Feedback

February Challenge 2014

Little Elephant and Movies, Draughts, Make Him Happy, Chef and Favourite Sequence, Longest Common Pattern, Little Elephant and Subarrays, Colored Array, Make It Zero 2

March Challenge 2014

Sereja and Sorting 2, Team Split, Binary Tournament, Walk, Maximum number, GCD condition, The Street , Little Chef and Numbers, Mike and Stamps, A Story with Strings, Chef and Graph Queries

April Challenge 2014

Sereja and Permutation, Counting Matrices, Farmer Feb, Cards, bags and coins, Chef and Digits, Divide the Tangerine, Chef and Tree Game, Shortest Path in Binary Trees

May Challenge 2014

Little Elephant and Balloons, Sereja and Game, Compilers and Parsers, Dynamic Trees and Queries, Chef-jumping, Fun with AGp, Sereja and Subsegment Increasings, Chef and Strange Matrix, Stone

June Challenge 2014

Little Elephant and Blocks, Maxim and Progressions, Chef and Functions, Chef and Digit Jumps, DARTS501, Chef and Subarray, Two Companies, Guessing Game, Forgot Password

July Challenge 2014

Little Elephant and Painting, Garden Game, Chef and Frogs, Sereja and Equality, Chef and Rectangle Genome, Count Substrings, Reach The Point, Dish Owner, Lucky Game, Game of Numbers

August Challenge 2014

Mountain Holidays 2, Sereja and Shuffling, Little Elephant and T-Shirts, Chef and Reversing, Team Sigma and Fibonacci, The Leaking Robot, Push the Flow!, Earthquake, Cleaning Tables, Chef and Gift

September Challenge 2014

Factorisation, Sereja and Bubble Sort, Chef and Rainbow Array - 2, Chef and Swaps, Chef and Left-Right, Chef and sequence, Fun with Rotation, Flooring

December Challenge 2014

Chef Under Pressure, Alok-nath and His Sanskars, Chef and Bracket-Pairs, Divide or die, Kali and Devtas, XOR with Subset, Course Selection, Chef and Apple Trees, Sereja and GCD, Good galaxy

January Challenge 2015

Queries on the String, Sereja and Number Division 2, Chef and A Large Permutation, Sereja and LCM, Chef and Stones, Sereja and Votes, One Dimensional Kingdoms, Xor Queries, Ranka, Gcd Queries

February Challenge 2015

Chef and Chain, Time to Study Graphs with Chef, Chef and Strange Formula, Chef and Strings, Let us play with rank list, Xor Matrix, Jigsaw Puzzle Solving, Chef and Equality, Devu and Locks

August Challenge 2015

Way Out, Social Cluster, Gravity Guy, Devu And Churu , Cooking Machine, Aditi and Magic Trick, Chef and insomnia, Future of draughts, Chef and Path

September Challenge 2015

Filling the maze, 3D Queries, Chain of Doughnuts, Nikitosh and xor, Count Steps in Matrix, Terrible vectors, Bank robbery, Lighthouses, Cracking the Code, Chef and Chetris

October Challenge 2015

Time measure, Count Subarrays, Who dares to be a millionaire, Spheres, Cyclic shifts in permutation, Rupsa and Equilateral Triangle

December Challenge 2015

Sereja and Dividing, Chef and cinema, Chef and the stones, Plane Division, Oracle Devu and Longest Common Subsequence, Misha and Permutation, Chef and Filters, Chef and Girls, Tanks

September Mega Cook-Off 2015

Reign 2, Forgotten Language, Super Numbers, Stacks

October Cook-Off 2015

Palindrome Pairs, Word Stem, Almost Sorted Permutation

November Cook-Off 2015

Sereja and Line, Sereja and Array and Subtracting, Sereja and Pairs, Sereja and Tree, Sereja and Tree 2

December Cook-Off 2015

Chef and Subarrays, Chef and LCS

October Lunchtime 2015

emitL, Save the nature, Fast squarer, Estimating progress

November Lunchtime 2015

Chef And A Complete Graph, Query over Matrix, Black And White Cells, Product on Tree

December Challenge 2016

Train Partner, Kth Max Subarray, Chef and Finding Direction, Sereja and Increasing subsequence, Kirito in labyrinth, Edit Distance Revisited, Roses for Alexey, Our Base is Under Attack, Bear and Three Colours

March Cook-Off 2016

Digital clock, Alternating subarray prefix

April Cook-Off 2016

Movie Weekend, Odd Divisors, Queries on a Binary Tree

November Cook-Off 2016

Sebi and the cube, Sebi and the highway, Sebi and the black money, Sebi and the corrupt goverment

October Lunchtime 2016

Restore the Permutation, FastFood Combos, The Largest Bouquet

February Cook-Off 2017

Download file, To add or to multiply game, Mixing flavors, Chairs, Cooking Game

June Cook-Off 2017

Ada and crayons, Knight Covering, A Study in Bake Street, SnackUp, Centeroid

December Cook-Off 2017

Minimum SubArray, Rotate Point, Beautiful Array, Football Match

April Cook-off 2018 Division 1

Run Direction, Binary Nim, Pawn Chess, Chef Goro

May Challenge 2020 Division 1

Buying a New String, Triple Sort, Binary Land, Sorting Vases, Not a Real World Problem, Chef and Rainbow Road, Chef and Bitwise Product, (Challenge) Nanobots, Precise Pairing, Precise Bipartite Pairing

December Lunchtime 2020 Division 1 (Unrated)

Even Sequence, Three Letters, One Zero Swaps

SnackDown 2021 - Online Qualifiers

Lucky Number

SnackDown 2021 - Online Round 1A

Round Robin Ranks , Dance Moves, Min Max LCM

SnackDown 2021 - Online Round 1B

Insider Subsequences, Help Utkarsh, Queens Placement , Largest Laddu, Help Nishant

SnackDown 2021 - Online Pre-Elimination

Non-Decreasing Subsequence of size K, Product Pain, Guests like slippers

SnackDown 2021 - Online Elimination Round (Rated for all)

Random Convex Hull, Graduate Work Matters, Sorting Segments

Problems Authored (10)

Problems Tested (13)

Editorials Contributed (5)