Problems

Note that you can solve most task in any order!
Already solved ones are at the bottom of the table.

Volume:

Simple Implementation Algorithms Puzzles Special

all tags

Id	Title	Translations	Author	Solved	Blessing
1	Sum "A+B"	DE ES FR AR ZH RO RU SK		59395	1.00
2	Sum in Loop	DE ES FR AR ZH RO RU SK		36011	1.87
3	Sums in Loop	DE ES FR AR ZH RO RU SK		27456	2.34
4	Minimum of Two	DE ES FR AR ZH RO RU SK		23931	2.58
5	Minimum of Three	DE ES FR AR ZH RO RU SK		21428	2.77
15	Maximum of array	DE ES AR ZH RO RU SK		18732	3.00
6	Rounding	DE ES AR ZH RO RU SK		17171	3.16
7	Fahrenheit to Celsius	DE ES AR ZH RO RU SK		16450	3.23
20	Vowel Count	DE ES AR ZH RO RU SK		13356	3.59
11	Sum of digits	DE ES RU ZH SK		13285	3.60
8	Arithmetic Progression	DE ES RU ZH SK		12483	3.71
41	Median of Three	DE ES AR ZH RO RU SK		11432	3.86
9	Triangles	DE ES RU ZH SK		11927	3.79
28	Body Mass Index	DE ES ZH RU SK		11301	3.88
13	Weighted sum of digits	DE ES RU ZH SK		10786	3.96
43	Dice Rolling	DE ES ZH RU SK		9708	4.15
16	Average of an array	DE ES RU SK		10224	4.06
30	Reverse String	DE ES RU SK		9656	4.16
17	Array Checksum	DE ES RU SK		9503	4.18
21	Array Counters	DE ES RU SK		8842	4.31
10	Linear Function	DE ES RU SK		8595	4.36
48	Collatz Sequence	DE ES RU SK		7669	4.56
12	Modulo and time difference	DE ES RU SK		7802	4.53
14	Modular Calculator	ES SK		7217	4.66
27	Bubble Sort	ES RU SK		6544	4.83
26	Greatest Common Divisor	ES SK RU		6370	4.88
18	Square Root	ES RU		6195	4.93
29	Sort with Indexes	RU		5907	5.01
50	Palindromes	DE ES RU SK		5453	5.15
23	Bubble in Array	ES RU		5655	5.08
52	Pythagorean Theorem	RU		5246	5.22
31	Rotate String	ES RU		5421	5.16
67	Fibonacci Sequence	RU		4699	5.41
68	Bicycle Race	ES RU		4667	5.42
24	Neumann's Random Generator	DE ES RU		5054	5.28
57	Smoothing the Weather	ES RU		4653	5.42
35	Savings Calculator			4480	5.49
104	Triangle Area	ES		3738	5.80
25	Linear Congruential Generator	RU		4410	5.52
32	Josephus Problem	RU		4295	5.56
44	Double Dice Roll	RU		4177	5.61
81	Bit Count	RU		3743	5.80
19	Matching Brackets	ES RU		4057	5.66
58	Card Names			3575	5.88
49	Rock Paper Scissors			3631	5.85
47	Caesar Shift Cipher	SK		3636	5.85
128	Combinations Counting			2942	6.22
55	Matching Words			3493	5.92
94	Fool's Day 2014	SK		3054	6.15
59	Bulls and Cows			3163	6.09
61	Prime Numbers Generation	RU		3104	6.13
22	Two Printers	ES RU		3368	5.99
42	Blackjack Counting			2884	6.25
120	Selection Sort			2281	6.66
38	Quadratic Equation			2672	6.39
33	Parity Control	RU		2600	6.43
53	King and Queen			2329	6.63
34	Binary Search			2414	6.56
171	Tree Height Measurement			1617	7.26
37	Mortgage Calculator	ZH		2255	6.68
45	Cards Shuffling	ZH		2206	6.72
69	Fibonacci Divisibility			2046	6.85
63	Integer Factorization	ZH		1964	6.92
46	Tic-Tac-Toe	ZH		2027	6.87
62	Prime Ranges			1800	7.07
72	Funny Words Generator			1739	7.13
121	Insertion Sort			1520	7.37
75	Yacht or Dice Poker			1649	7.23
172	Cloud Altitude Measurement			1219	7.75
39	Share Price Volatility			1680	7.19
127	Anagrams			1356	7.56
134	Flying Text Screensaver			1253	7.70
156	Luhn Algorithm	SK		1099	7.93
114	Tricky Printing			1183	7.80
80	Duel Chances			1251	7.70
36	Code Guesser	UA		1345	7.58
74	Clock Hands			1175	7.81
135	Variable Length Code			987	8.12
54	Pythagorean Triples			1163	7.83
105	Convex Polygon Area			1016	8.07
73	Hexagonal Grid			1047	8.01
145	Modular Exponentiation			858	8.36
97	Girls and Pigs			936	8.21
116	Summing Up			860	8.36
181	Reverse Polish Notation			661	8.81
98	Azimuth at Treasure Island			813	8.45
122	QuickSort			751	8.59
51	Dungeons and Dragons Dice	UA		891	8.29
85	Rotation in 2D Space			819	8.44
40	Paths in the Grid	UA		904	8.27
187	Static Web Page			612	8.95
56	Life is Simple			853	8.37
188	Basics of HTML			583	9.03
66	Caesar Cipher Cracker			778	8.53
70	Most Frequent Word			768	8.55
88	Pitch and Notes			720	8.66
87	Tree Builder			686	8.75
108	Star Medals			634	8.88
60	Sweet Harvest			707	8.69
95	Simple Linear Regression			647	8.85
77	Point to Segment Distance			656	8.82
495	Counting Arithmetic Progressions		csfpython	2	18.19
428	Broken Keyboard			100	12.08
86	Brainfuck Interpreter			599	8.98
211	Information Entropy			413	9.63
71	Fibonacci Divisibility Advanced			611	8.95
91	Game of 2048			577	9.05
207	Suffix Array			401	9.68
480	Coin Payments		csfpython	22	14.65
101	Gradient Calculation			534	9.18
143	Extended Euclidean Algorithm			471	9.40
494	Holiday Travel		csfpython	3	17.69
176	Say 100			424	9.58
82	Levenshtein Distance			543	9.15
191	Spaceship Weight Fraud			387	9.74
119	Brain Fibo			472	9.40
485	Magic 3		csfpython	14	15.39
89	Instrument Tuner			508	9.27
206	Base-32 Encoding			358	9.87
64	Maze Pathfinder			531	9.19
195	Mul Two			370	9.82
79	Cycles Detection			496	9.31
92	Binary Heap			465	9.42
131	Four Pics One Word			406	9.66
154	Breadth First Search			378	9.78
487	Reduce and Equalise		csfpython	10	15.93
83	Graph Generator			454	9.46
476	Prime Vowel Count		csfpython	22	14.65
301	Skyscraper Price			202	10.87
136	Variable Length Code Unpack			369	9.82
90	Lexicographic Permutations			410	9.64
78	Bezier Curves			422	9.59
496	Minimum Journey Cost		csfpython	-	20.10
189	Dynamic Web Page			307	10.14
150	Introducing Regexps			346	9.93
155	Depth First Search			341	9.96
126	Sequence of Squares			366	9.84
65	Transitive Closure on Candy States			420	9.60
385	Number of steps in Euclidean Algorithm		gardengnome	106	11.98
167	Copy Line			311	10.12
170	Binary Search in Array			306	10.15
99	Uphill Shooting			362	9.86
197	Loops in Assembly			269	10.37
161	Topological Sorting			298	10.19
461	Lucky 7		csfpython	31	14.07
117	Divide by Two			336	9.98
144	Modular Inverse			302	10.17
377	Sum of Digits Divisibility			102	12.04
429	Moving Average in Time			55	13.10
76	Pawn Move Validator			340	9.96
174	Calculation of Pi			260	10.43
425	Explosive Breeding			57	13.04
492	Fastest Clearance		csfpython	3	17.69
93	Starving Priority Queue			319	10.07
133	Billiard Ball			283	10.28
96	Snake Arcade			306	10.15
140	Proper Bracket Sequences			271	10.36
165	Safe Landing			251	10.49
481	Field Trip		csfpython	11	15.78
184	Matches Picking		quandray	225	10.68
103	Easter Eggs			283	10.28
123	Knapsack of Integers			267	10.38
84	Dijkstra in the Network			291	10.23
484	A Message from Deep Space		csfpython	8	16.28
173	Chords of Music			220	10.72
190	Query String Parameters			208	10.81
130	Combinations with Repetitions			248	10.51
125	Bogosort			246	10.52
444	White Rectangle			34	13.92
109	Lucky Tickets			255	10.46
471	Missing Digits		csfpython	16	15.17
472	Unreachable Amounts		csfpython	15	15.28
323	Next Palindrome		csfpython	106	11.98
146	Color Cubes			214	10.77
366	Image Cutting		oezguery	79	12.48
129	Enumerating Combinations			221	10.71
371	Pages to Print			73	12.62
151	Word Ladders			201	10.87
164	Page Rank			191	10.96
139	Beam Balance and Masses			205	10.84
208	Neighborhood of a String			164	11.23
253	Beautiful Line Chart			136	11.55
138	Huffman Coding			199	10.89
374	Longest Common Subsequence			67	12.76
437	Elections and Happiness			32	14.02
360	Whisky Blending		csfpython	74	12.59
194	Convex Hull and Farmers			164	11.23
201	Point in Polygon			157	11.30
482	SS Numbers		csfpython	7	16.48
478	Robot Deliveries		csfpython	9	16.10
152	RSA Cryptography			179	11.07
468	The Garden of Words		zelevin	14	15.39
433	A Crime on Logic Island		csfpython	32	14.02
137	Shannon-Fano Coding			184	11.03
111	Necklace Count			197	10.91
337	Introducing Zeckendorf		csfpython	81	12.44
102	Travelling Salesman			198	10.90
489	TV Charity Fundraiser		csfpython	3	17.69
491	Lucky Number Scores		csfpython	2	18.19
493	Ternary Logic			1	18.89
399	Methane Identification		moxieman	47	13.37
192	Gangster Battles			148	11.40
110	Lucky Tickets Advanced			186	11.01
244	Introducing SQL			121	11.75
199	Employees Web App			142	11.47
269	Fibonacci coding			105	11.99
329	Roman Arithmetic		csfpython	77	12.53
368	Number Base Palindrome		csfpython	58	13.01
148	Public Key Cryptography Intro			152	11.36
106	Random Search Optimization			168	11.18
245	Aggregations in SQL			107	11.96
294	Vigenere Cipher			86	12.34
490	Circuit Board Connections		csfpython	2	18.19
124	Knapsack Backtracking			158	11.29
168	Caesar meets BF			138	11.52
162	Rubik's Cube			139	11.51
202	Dancing Pairs			122	11.74
214	Sick Travellers			115	11.84
179	Look and Say binary			129	11.64
182	Frodo and Black Riders			122	11.74
198	Prn Hex Str			113	11.87
177	Nim Game			119	11.78
160	Social Web Scraper			125	11.69
246	Joins in SQL			92	12.22
158	Hamming Codes			124	11.71
185	Simple 3D Scene			112	11.88
157	Emirp primE			122	11.74
414	MIDI Variable Length Numbers			29	14.19
364	Arthur Engel's Randomizer			47	13.37
258	Text Justification			84	12.38
359	Find 3 Numbers		csfpython	48	13.33
466	Dictionary Entries		csfpython	10	15.93
449	Space Pirates		csfpython	16	15.17
477	Lottery Balls		csfpython	6	16.71
459	Number String Multiples of Thirteen		csfpython	12	15.64
401	Methane Rotation		moxieman	31	14.07
488	Accurate Curve Fitting		csfpython	2	18.19
159	Hard Life			110	11.91
372	String Minimization			40	13.64
100	Crossing the Road			128	11.65
463	Crossing Towns		csfpython	10	15.93
153	Fermat goes hacking RSA			110	11.91
447	Fixed Product, Minimum Sum		csfpython	15	15.28
475	Medieval Medicine		zelevin	6	16.71
418	Expected Number of Random Moves		moxieman	24	14.50
265	Update in SQL			72	12.64
411	Elo Ratings		moxieman	26	14.37
324	Merge Sort			52	13.20
115	Gradient Descent for SLE			116	11.82
474	Reachable Amounts		gardengnome	6	16.71
291	Squirrels vs. Acorns		zelevin	61	12.93
281	Basic Tokenizer			64	12.84
384	Equal Hamming Distance		csfpython	33	13.97
196	Fibonacci Randomizer			89	12.28
141	Sliding Window Search			105	11.99
277	The Adventure of Morse Code		zelevin	64	12.84
186	Simple 3D Scene (cont)			89	12.28
469	Game of Generals			7	16.48
483	Sixes and Sevens		csfpython	3	17.69
427	Cheapest Bus Tickets			19	14.89
112	Travelling Salesman Inverted			108	11.95
193	Maximum Flow			85	12.36
210	Ticket Puzzle			80	12.46
458	Mountain Panorama		csfpython	10	15.93
166	Page Rank as Eigenvector			92	12.22
142	LZ77 decompression			98	12.11
209	Suffix Array Advanced			79	12.48
486	Two Colour Special Nim		csfpython	2	18.19
460	Carlsdale Caverns		csfpython	9	16.10
113	Ground Zero			102	12.04
452	Implication in Logic			11	15.78
216	Cracking Linear Congruential Generator			73	12.62
203	Tic-Tac-Toe Minimax Algorithm			76	12.55
219	Neural Network Calculation			71	12.67
274	Two Buckets			56	13.07
434	A Crime on Logic Island Advanced		csfpython	15	15.28
400	Memory Check			23	14.57
464	Graph to Loops Decomposition			7	16.48
132	Stream Cipher Breaking			87	12.32
107	Knight's Tour			93	12.20
351	Nicomachus			34	13.92
163	Colliding Balls			78	12.50
259	Easter Bunnies		gardengnome	55	13.10
241	Village Ways			59	12.98
467	Permutation Generator		csfpython	6	16.71
381	Finding Squares		csfpython	26	14.37
175	Algae Robot			73	12.62
457	Railroad and Hamilton			8	16.28
205	Clustering the Stars			64	12.84
230	Move-To-Front Transform			57	13.04
446	Hangman			10	15.93
293	Sums of Triplets			43	13.52
315	Count the Common Factors		csfpython	38	13.73
403	Hi-Lo dice game			19	14.89
445	Formula 1			10	15.93
407	River Labyrinth			18	14.98
335	Venus Visible			33	13.97
435	Maze Mapping API-Robot			12	15.64
406	Wormholes of Cygnus		moxieman	18	14.98
473	Skittles		csfpython	4	17.30
218	Rain Must Fall	DE		57	13.04
204	Wandering Star			59	12.98
453	SR latch			8	16.28
334	Find all of the SETs		csfpython	32	14.02
200	Fizz Buzz in Asm			59	12.98
292	Factorial Trailing Zeroes			40	13.64
436	Avoid the Grid Points		csfpython	11	15.78
149	Prime Chains			67	12.76
255	LCM of a range			46	13.41
257	Missing Records in SQL			45	13.44
212	BCD to Hex			53	13.17
412	Json Fix			15	15.28
390	Card Pairing Solitaire			19	14.89
438	Maze Generator			10	15.93
421	Princess and Tiger			13	15.51
118	Maxit Single-Player			68	12.74
233	Language Study			47	13.37
307	The Problem of Too Many Clues		zelevin	33	13.97
423	Russian Dolls		csfpython	12	15.64
440	Mud Walker			9	16.10
223	Introducing Scheme			47	13.37
147	Color Cubes Advanced			60	12.95
180	Simple Game of Sticks			54	13.13
178	Maze of the Wumpus			54	13.13
450	Bead Games		csfpython	7	16.48
379	Dice with Infinity Sides		telebashna	19	14.89
247	Towers of Hanoi			41	13.60
442	Chomp			8	16.28
229	Burrows-Wheeler Transform			42	13.56
376	Cartesian Tree Visualization			18	14.98
465	Red Blue Hackenbush		csfpython	4	17.30
420	Life on a String		csfpython	11	15.78
439	Power Sum of Digits		csfpython	8	16.28
426	Weighted Sum of Digits 2		csfpython	10	15.93
451	Maximize Toy Production		csfpython	6	16.71
352	Hurkle			21	14.73
299	Tree Visualizer			29	14.19
357	Ulam's Prime Spiral			20	14.81
330	Easter Bunnies Are Back		gardengnome	24	14.50
183	Connect Four			46	13.41
388	Fibonacci Guessing Game			15	15.28
347	Unwanted Multiples		csfpython	21	14.73
297	Collatz in the Range			28	14.25
338	Throwing Easter Eggs		gardengnome	22	14.65
455	D flip-flop			5	16.98
270	Hexlife			31	14.07
284	Rotate Array In-Place			29	14.19
354	Too Many Divisors		csfpython	19	14.89
454	Multiplexer 4x4			5	16.98
296	Tree Value	RU	csfpython	27	14.31
409	Election Fever		csfpython	11	15.78
349	Burrows		gardengnome	19	14.89
290	Every Leaf on Every Tree		zelevin	26	14.37
405	Three Friendly Knights		csfpython	11	15.78
389	Binary Split Guessing Game		csfpython	13	15.51
234	Train Merge			33	13.97
286	Self-Printing Program			26	14.37
238	Bear Hunt			32	14.02
243	Grille Encryption			31	14.07
346	Long Decimal Fractions		csfpython	18	14.98
353	Hurkle Hunter			17	15.07
249	Turing Increment			30	14.13
256	Rook Jump Maze			29	14.19
312	The Shredder Conundrum		zelevin	22	14.65
392	Fixing an Anagram			12	15.64
287	Palindrome Frog		csfpython	25	14.44
432	Ball Bearing Collisions		csfpython	7	16.48
375	Space Invaders			14	15.39
217	Personality Swap			33	13.97
340	Zeckendorf Lite		csfpython	18	14.98
298	Revoltle		zelevin	23	14.57
331	Rotating Toy Display		csfpython	19	14.89
339	Parking Lot			18	14.98
261	Easter Bunnies 2D		gardengnome	27	14.31
362	Euclid, Manhattan and Chebyshev			15	15.28
268	Logic Transformation			26	14.37
300	Run-Length Encoding			22	14.65
169	Automated Landing			37	13.78
393	Urban Planning		csfpython	11	15.78
462	Rota Boards		csfpython	3	17.69
417	Unfortunate Bubble Sort		gardengnome	8	16.28
408	Mad Beaver in River Labyrinth			9	16.10
363	Language Detector			14	15.39
470	Shogi Engine			2	18.19
479	Robot and the Wall			1	18.89
415	Smallest Message		gardengnome	8	16.28
295	Vigenere Cipher Cracker			21	14.73
313	Seven Segment Decoder			19	14.89
285	Rotate Matrix In Place			22	14.65
395	Growth of Micro-Organisms		csfpython	10	15.93
367	Roguelike 1d			13	15.51
282	Predictable Board Game		csfpython	22	14.65
319	Tower of Hanoi Rules		csfpython	18	14.98
271	A Knight some Trolls and a Princess		csfpython	23	14.57
431	King and Rook Checkmate			6	16.71
250	Turing Clone			25	14.44
382	Die Throw Sequences		csfpython	11	15.78
314	The Sorites Solution		zelevin	18	14.98
275	Three Buckets			22	14.65
361	Rogue Mazes			13	15.51
398	Collecting Diamonds		csfpython	9	16.10
358	Mandelbrot Set			13	15.51
386	Advent Calendar Chocolate		gardengnome	10	15.93
344	Throwing Easter Eggs Part 2		gardengnome	14	15.39
456	Every Third Bit			3	17.69
383	E2C2S - try harder!		gardengnome	10	15.93
424	New Towers of Hanoi		csfpython	6	16.71
231	Dice Black Jack			24	14.50
443	Football League Tables		csfpython	4	17.30
341	Zeckendorf Advanced		csfpython	13	15.51
419	Special Digits		csfpython	6	16.71
441	Max versus Min		csfpython	4	17.30
260	Low Cost Road Network		csfpython	20	14.81
213	Micro-Life	SK		24	14.50
220	Neural Network Training			23	14.57
416	Socket Server		testuser	6	16.71
332	Easter Bunnies 2D Are Back		gardengnome	13	15.51
402	Game of Stones		csfpython	7	16.48
222	Easter Eggs Advanced			22	14.65
413	Tree Painting		csfpython	6	16.71
254	Rule 30 by Turing			19	14.89
266	Pancake Sorting			18	14.98
387	Big Numbers		csfpython	8	16.28
289	The Case of the Desperate Mastermind		zelevin	16	15.17
448	Button Cycles		csfpython	3	17.69
263	Easter Bunnies 3D		gardengnome	18	14.98
262	Easter Bunnies 2D Advanced		gardengnome	18	14.98
336	Currency Arbitrage			12	15.64
410	Village Door Shuffle		csfpython	6	16.71
422	Mabinogion Sheep		moxieman	5	16.98
221	XWords		quandray	21	14.73
343	Village of Ticks			11	15.78
316	Apogee			13	15.51
288	Langton's Ant		csfpython	15	15.28
235	Train Merge Advanced			19	14.89
326	Sum Them Forth			12	15.64
391	Scout Proficiency Badges		csfpython	7	16.48
311	The Mirror Maze		zelevin	13	15.51
404	Methane Normalization		moxieman	6	16.71
350	Colourful Egg Sequences		gardengnome	10	15.93
430	Cutting Paper		csfpython	4	17.30
320	Accordion		pearlbarley	12	15.64
279	Two Buckets Advanced		csfpython	15	15.28
306	Line Drawing Algorithm			13	15.51
305	The Catacombs of Chronos		zelevin	13	15.51
276	Lucky Pairs		csfpython	15	15.28
303	Towers Under Cover			13	15.51
267	Turing Maze			15	15.28
309	Board Game Sequences		csfpython	12	15.64
380	Treap Study			7	16.48
365	Flower Border Arrangements		csfpython	8	16.28
394	Many Shortest Routes		csfpython	6	16.71
333	Happy Triplets			10	15.93
242	Comment Stripper			16	15.17
224	Transposing List of Lists			17	15.07
345	Elliptic Curves Basics			9	16.10
237	Road Network Destruction			16	15.17
264	Party Presents		csfpython	14	15.39
227	Hashtable Implementation			16	15.17
304	Ordered Brackets		csfpython	11	15.78
397	Trading Bot			5	16.98
327	Dobbin's Long Journey		csfpython	9	16.10
378	Space Invaders Automation			6	16.71
310	Board Game Sequences Advanced		csfpython	10	15.93
325	Ultimate Sort Trial			9	16.10
342	Adaptive Arithmetic Coding			8	16.28
322	Gray Decoder			9	16.10
321	Hanoi Tower Heights		csfpython	9	16.10
373	Railroad Rat		csfpython	6	16.71
225	Hamurabi			14	15.39
369	Flappy Bird			6	16.71
328	Beep Beep Beep			8	16.28
252	Shadok and Gibis			12	15.64
308	Circle Drawing Algorithm			9	16.10
283	Predictable Board Game on 10 Boards		csfpython	10	15.93
302	Sound-Controlled Robot			9	16.10
278	Polyomino Generation			10	15.93
215	Klotski	SK		13	15.51
251	Radio Spies			11	15.78
370	Jewels			5	16.98
280	Three Buckets Re-visited		csfpython	9	16.10
226	Multiplicative Persistence Backtrace			11	15.78
232	Shift Register Randomizer			10	15.93
348	Trick-Taking Game			5	16.98
273	Logic Glitches			8	16.28
248	Christmas Puzzle			9	16.10
396	Chocolate Triangles and BF		moxieman	3	17.69
240	Playfair Cipher Cracking			9	16.10
239	Foxes and Geese			9	16.10
236	Is the Earth Flat			9	16.10
272	Hexplore			7	16.48
355	Robots Game			4	17.30
228	Maze Mapping Robot			8	16.28
356	Robots Game Autoplay			3	17.69
317	Launch to Orbit			4	17.30
318	Launch to Orbit automated			2	18.19