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		59405	1.00
2	Sum in Loop	DE ES FR AR ZH RO RU SK		36015	1.87
3	Sums in Loop	DE ES FR AR ZH RO RU SK		27460	2.34
4	Minimum of Two	DE ES FR AR ZH RO RU SK		23935	2.58
5	Minimum of Three	DE ES FR AR ZH RO RU SK		21431	2.77
15	Maximum of array	DE ES AR ZH RO RU SK		18734	3.00
6	Rounding	DE ES AR ZH RO RU SK		17174	3.16
7	Fahrenheit to Celsius	DE ES AR ZH RO RU SK		16451	3.23
20	Vowel Count	DE ES AR ZH RO RU SK		13358	3.59
11	Sum of digits	DE ES RU ZH SK		13287	3.60
8	Arithmetic Progression	DE ES RU ZH SK		12484	3.71
41	Median of Three	DE ES AR ZH RO RU SK		11434	3.86
9	Triangles	DE ES RU ZH SK		11928	3.79
28	Body Mass Index	DE ES ZH RU SK		11302	3.88
13	Weighted sum of digits	DE ES RU ZH SK		10789	3.96
43	Dice Rolling	DE ES ZH RU SK		9710	4.15
16	Average of an array	DE ES RU SK		10228	4.06
30	Reverse String	DE ES RU SK		9659	4.16
17	Array Checksum	DE ES RU SK		9506	4.18
21	Array Counters	DE ES RU SK		8845	4.31
10	Linear Function	DE ES RU SK		8596	4.36
48	Collatz Sequence	DE ES RU SK		7670	4.56
12	Modulo and time difference	DE ES RU SK		7803	4.53
14	Modular Calculator	ES SK		7219	4.66
27	Bubble Sort	ES RU SK		6544	4.83
26	Greatest Common Divisor	ES SK RU		6371	4.88
18	Square Root	ES RU		6197	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	5.09
52	Pythagorean Theorem	RU		5248	5.22
31	Rotate String	ES RU		5421	5.16
67	Fibonacci Sequence	RU		4701	5.41
68	Bicycle Race	ES RU		4668	5.42
24	Neumann's Random Generator	DE ES RU		5054	5.28
57	Smoothing the Weather	ES RU		4656	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		4296	5.56
44	Double Dice Roll	RU		4177	5.61
81	Bit Count	RU		3743	5.80
19	Matching Brackets	ES RU		4060	5.66
58	Card Names			3578	5.88
49	Rock Paper Scissors			3632	5.85
47	Caesar Shift Cipher	SK		3639	5.85
128	Combinations Counting			2943	6.22
55	Matching Words			3496	5.92
94	Fool's Day 2014	SK		3055	6.15
59	Bulls and Cows			3166	6.09
61	Prime Numbers Generation	RU		3108	6.12
22	Two Printers	ES RU		3370	5.98
42	Blackjack Counting			2888	6.25
120	Selection Sort			2283	6.66
38	Quadratic Equation			2674	6.39
33	Parity Control	RU		2603	6.43
53	King and Queen			2334	6.62
34	Binary Search			2416	6.56
171	Tree Height Measurement			1619	7.26
37	Mortgage Calculator	ZH		2259	6.68
45	Cards Shuffling	ZH		2209	6.72
69	Fibonacci Divisibility			2051	6.85
63	Integer Factorization	ZH		1970	6.92
46	Tic-Tac-Toe	ZH		2029	6.87
62	Prime Ranges			1804	7.07
72	Funny Words Generator			1743	7.13
121	Insertion Sort			1521	7.37
75	Yacht or Dice Poker			1651	7.22
172	Cloud Altitude Measurement			1221	7.75
39	Share Price Volatility			1682	7.19
127	Anagrams			1356	7.57
134	Flying Text Screensaver			1254	7.70
156	Luhn Algorithm	SK		1102	7.93
114	Tricky Printing			1184	7.80
80	Duel Chances			1253	7.70
36	Code Guesser	UA		1346	7.58
74	Clock Hands			1177	7.81
135	Variable Length Code			989	8.11
54	Pythagorean Triples			1167	7.83
105	Convex Polygon Area			1019	8.06
495	Counting Arithmetic Progressions		csfpython	4	17.30
73	Hexagonal Grid			1050	8.01
145	Modular Exponentiation			861	8.35
97	Girls and Pigs			940	8.20
116	Summing Up			862	8.35
181	Reverse Polish Notation			662	8.81
98	Azimuth at Treasure Island			815	8.45
51	Dungeons and Dragons Dice	UA		896	8.28
122	QuickSort			753	8.59
496	Minimum Journey Cost		csfpython	1	18.89
85	Rotation in 2D Space			822	8.43
40	Paths in the Grid	UA		905	8.27
187	Static Web Page			613	8.94
56	Life is Simple			856	8.36
188	Basics of HTML			583	9.03
66	Caesar Cipher Cracker			780	8.52
70	Most Frequent Word			771	8.54
88	Pitch and Notes			721	8.66
87	Tree Builder			686	8.75
494	Holiday Travel		csfpython	4	17.30
108	Star Medals			635	8.88
60	Sweet Harvest			710	8.69
95	Simple Linear Regression			648	8.85
77	Point to Segment Distance			657	8.82
428	Broken Keyboard			102	12.04
86	Brainfuck Interpreter			599	8.98
211	Information Entropy			413	9.63
71	Fibonacci Divisibility Advanced			613	8.94
91	Game of 2048			577	9.05
207	Suffix Array			401	9.68
101	Gradient Calculation			536	9.18
480	Coin Payments		csfpython	22	14.65
143	Extended Euclidean Algorithm			472	9.40
176	Say 100			424	9.58
82	Levenshtein Distance			545	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			509	9.27
64	Maze Pathfinder			534	9.18
206	Base-32 Encoding			358	9.87
195	Mul Two			370	9.82
79	Cycles Detection			496	9.31
92	Binary Heap			465	9.42
131	Four Pics One Word			407	9.65
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
78	Bezier Curves			423	9.59
90	Lexicographic Permutations			410	9.64
155	Depth First Search			343	9.95
150	Introducing Regexps			346	9.93
189	Dynamic Web Page			307	10.14
126	Sequence of Squares			366	9.84
65	Transitive Closure on Candy States			423	9.59
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			363	9.85
197	Loops in Assembly			269	10.37
161	Topological Sorting			299	10.19
461	Lucky 7		csfpython	31	14.07
117	Divide by Two			336	9.98
144	Modular Inverse			304	10.16
377	Sum of Digits Divisibility			102	12.04
429	Moving Average in Time			56	13.07
76	Pawn Move Validator			341	9.96
174	Calculation of Pi			261	10.42
425	Explosive Breeding			57	13.04
492	Fastest Clearance		csfpython	3	17.69
93	Starving Priority Queue			319	10.07
133	Billiard Ball			284	10.28
96	Snake Arcade			307	10.14
140	Proper Bracket Sequences			273	10.34
165	Safe Landing			252	10.48
481	Field Trip		csfpython	11	15.78
493	Ternary Logic			2	18.19
184	Matches Picking		quandray	225	10.68
103	Easter Eggs			283	10.28
123	Knapsack of Integers			268	10.38
84	Dijkstra in the Network			292	10.23
484	A Message from Deep Space		csfpython	8	16.28
173	Chords of Music			220	10.72
130	Combinations with Repetitions			249	10.50
190	Query String Parameters			208	10.81
444	White Rectangle			35	13.87
125	Bogosort			247	10.52
109	Lucky Tickets			256	10.46
471	Missing Digits		csfpython	16	15.17
472	Unreachable Amounts		csfpython	15	15.28
323	Next Palindrome		csfpython	107	11.96
366	Image Cutting		oezguery	80	12.46
146	Color Cubes			215	10.76
129	Enumerating Combinations			221	10.71
371	Pages to Print			74	12.60
151	Word Ladders			201	10.87
164	Page Rank			192	10.95
208	Neighborhood of a String			166	11.20
139	Beam Balance and Masses			205	10.84
437	Elections and Happiness			33	13.97
253	Beautiful Line Chart			137	11.54
374	Longest Common Subsequence			68	12.74
138	Huffman Coding			200	10.88
360	Whisky Blending		csfpython	75	12.57
194	Convex Hull and Farmers			165	11.21
201	Point in Polygon			158	11.29
482	SS Numbers		csfpython	7	16.48
433	A Crime on Logic Island		csfpython	33	13.97
478	Robot Deliveries		csfpython	9	16.10
152	RSA Cryptography			180	11.06
337	Introducing Zeckendorf		csfpython	82	12.42
468	The Garden of Words		zelevin	14	15.39
137	Shannon-Fano Coding			185	11.02
111	Necklace Count			197	10.91
102	Travelling Salesman			199	10.89
399	Methane Identification		moxieman	48	13.33
489	TV Charity Fundraiser		csfpython	3	17.69
491	Lucky Number Scores		csfpython	2	18.19
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			106	11.98
368	Number Base Palindrome		csfpython	59	12.98
329	Roman Arithmetic		csfpython	77	12.53
148	Public Key Cryptography Intro			153	11.35
106	Random Search Optimization			168	11.18
124	Knapsack Backtracking			159	11.28
490	Circuit Board Connections		csfpython	2	18.19
294	Vigenere Cipher			86	12.34
245	Aggregations in SQL			107	11.96
168	Caesar meets BF			138	11.52
202	Dancing Pairs			123	11.72
162	Rubik's Cube			139	11.51
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
449	Space Pirates		csfpython	17	15.07
177	Nim Game			119	11.78
160	Social Web Scraper			125	11.69
414	MIDI Variable Length Numbers			30	14.13
158	Hamming Codes			125	11.69
246	Joins in SQL			92	12.22
364	Arthur Engel's Randomizer			48	13.33
185	Simple 3D Scene			112	11.88
157	Emirp primE			122	11.74
258	Text Justification			84	12.38
359	Find 3 Numbers		csfpython	48	13.33
466	Dictionary Entries		csfpython	10	15.93
477	Lottery Balls		csfpython	6	16.71
401	Methane Rotation		moxieman	32	14.02
459	Number String Multiples of Thirteen		csfpython	12	15.64
418	Expected Number of Random Moves		moxieman	26	14.37
488	Accurate Curve Fitting		csfpython	2	18.19
159	Hard Life			110	11.91
372	String Minimization			40	13.64
153	Fermat goes hacking RSA			111	11.90
100	Crossing the Road			128	11.65
463	Crossing Towns		csfpython	10	15.93
447	Fixed Product, Minimum Sum		csfpython	15	15.28
475	Medieval Medicine		zelevin	6	16.71
265	Update in SQL			72	12.64
411	Elo Ratings		moxieman	26	14.37
115	Gradient Descent for SLE			117	11.81
324	Merge Sort			52	13.20
291	Squirrels vs. Acorns		zelevin	62	12.90
281	Basic Tokenizer			65	12.82
474	Reachable Amounts		gardengnome	6	16.71
384	Equal Hamming Distance		csfpython	33	13.97
141	Sliding Window Search			106	11.98
277	The Adventure of Morse Code		zelevin	65	12.82
196	Fibonacci Randomizer			89	12.28
186	Simple 3D Scene (cont)			89	12.28
452	Implication in Logic			12	15.64
193	Maximum Flow			86	12.34
427	Cheapest Bus Tickets			19	14.89
483	Sixes and Sevens		csfpython	3	17.69
469	Game of Generals			7	16.48
166	Page Rank as Eigenvector			93	12.20
112	Travelling Salesman Inverted			108	11.95
210	Ticket Puzzle			80	12.46
458	Mountain Panorama		csfpython	10	15.93
142	LZ77 decompression			99	12.10
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
216	Cracking Linear Congruential Generator			74	12.60
467	Permutation Generator		csfpython	7	16.48
203	Tic-Tac-Toe Minimax Algorithm			77	12.53
219	Neural Network Calculation			72	12.64
274	Two Buckets			56	13.07
434	A Crime on Logic Island Advanced		csfpython	15	15.28
400	Memory Check			23	14.57
351	Nicomachus			35	13.87
132	Stream Cipher Breaking			88	12.30
464	Graph to Loops Decomposition			7	16.48
107	Knight's Tour			93	12.20
163	Colliding Balls			78	12.50
259	Easter Bunnies		gardengnome	55	13.10
241	Village Ways			59	12.98
381	Finding Squares		csfpython	26	14.37
175	Algae Robot			73	12.62
205	Clustering the Stars			65	12.82
457	Railroad and Hamilton			8	16.28
403	Hi-Lo dice game			20	14.81
230	Move-To-Front Transform			58	13.01
406	Wormholes of Cygnus		moxieman	19	14.89
335	Venus Visible			34	13.92
293	Sums of Triplets			43	13.52
446	Hangman			10	15.93
315	Count the Common Factors		csfpython	38	13.73
445	Formula 1			10	15.93
407	River Labyrinth			18	14.98
435	Maze Mapping API-Robot			12	15.64
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	12.77
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
376	Cartesian Tree Visualization			19	14.89
229	Burrows-Wheeler Transform			43	13.52
442	Chomp			8	16.28
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
349	Burrows		gardengnome	20	14.81
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
392	Fixing an Anagram			13	15.51
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
256	Rook Jump Maze			30	14.13
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
249	Turing Increment			30	14.13
353	Hurkle Hunter			17	15.07
312	The Shredder Conundrum		zelevin	22	14.65
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
344	Throwing Easter Eggs Part 2		gardengnome	15	15.28
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
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
260	Low Cost Road Network		csfpython	21	14.73
443	Football League Tables		csfpython	4	17.30
220	Neural Network Training			24	14.50
341	Zeckendorf Advanced		csfpython	13	15.51
419	Special Digits		csfpython	6	16.71
441	Max versus Min		csfpython	4	17.30
213	Micro-Life	SK		24	14.50
336	Currency Arbitrage			13	15.51
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
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
380	Treap Study			8	16.28
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
345	Elliptic Curves Basics			10	15.93
303	Towers Under Cover			13	15.51
267	Turing Maze			15	15.28
309	Board Game Sequences		csfpython	12	15.64
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
237	Road Network Destruction			16	15.17
342	Adaptive Arithmetic Coding			9	16.10
264	Party Presents		csfpython	14	15.39
227	Hashtable Implementation			16	15.17
322	Gray Decoder			10	15.93
369	Flappy Bird			7	16.48
304	Ordered Brackets		csfpython	11	15.78
397	Trading Bot			5	16.98
378	Space Invaders Automation			6	16.71
327	Dobbin's Long Journey		csfpython	9	16.10
310	Board Game Sequences Advanced		csfpython	10	15.93
325	Ultimate Sort Trial			9	16.10
321	Hanoi Tower Heights		csfpython	9	16.10
373	Railroad Rat		csfpython	6	16.71
302	Sound-Controlled Robot			10	15.93
225	Hamurabi			14	15.39
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
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
273	Logic Glitches			9	16.10
226	Multiplicative Persistence Backtrace			11	15.78
236	Is the Earth Flat			10	15.93
232	Shift Register Randomizer			10	15.93
348	Trick-Taking Game			5	16.98
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
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