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		55247	1.00
2	Sum in Loop	DE ES FR AR ZH RO RU SK		33808	1.85
3	Sums in Loop	DE ES FR AR ZH RO RU SK		25783	2.32
4	Minimum of Two	DE ES FR AR ZH RO RU SK		22456	2.56
5	Minimum of Three	DE ES FR AR ZH RO RU SK		20120	2.75
15	Maximum of array	DE ES AR ZH RO RU SK		17572	2.99
6	Rounding	DE ES AR ZH RO RU SK		16209	3.13
7	Fahrenheit to Celsius	DE ES AR ZH RO RU SK		15510	3.21
20	Vowel Count	DE ES AR ZH RO RU SK		12581	3.57
11	Sum of digits	DE ES RU ZH SK		12475	3.58
8	Arithmetic Progression	DE ES RU ZH SK		11674	3.70
41	Median of Three	DE ES AR ZH RO RU SK		10723	3.85
9	Triangles	DE ES RU ZH SK		11085	3.79
28	Body Mass Index	DE ES ZH RU SK		10587	3.87
13	Weighted sum of digits	DE ES RU ZH SK		10094	3.95
43	Dice Rolling	DE ES ZH RU SK		9101	4.13
16	Average of an array	DE ES RU SK		9547	4.05
30	Reverse String	DE ES RU SK		8990	4.15
17	Array Checksum	DE ES RU SK		8849	4.18
21	Array Counters	DE ES RU SK		8250	4.30
10	Linear Function	DE ES RU SK		7970	4.36
48	Collatz Sequence	DE ES RU SK		7194	4.54
12	Modulo and time difference	DE ES RU SK		7319	4.51
14	Modular Calculator	ES SK		6765	4.65
27	Bubble Sort	ES RU SK		6101	4.83
26	Greatest Common Divisor	ES SK RU		5954	4.87
18	Square Root	ES RU		5727	4.94
29	Sort with Indexes	RU		5509	5.00
50	Palindromes	DE ES RU SK		5053	5.15
23	Bubble in Array	ES RU		5289	5.08
52	Pythagorean Theorem	RU		4849	5.23
31	Rotate String	ES RU		5044	5.16
67	Fibonacci Sequence	RU		4373	5.41
68	Bicycle Race	ES RU		4343	5.42
57	Smoothing the Weather	ES RU		4375	5.40
24	Neumann's Random Generator	DE ES RU		4726	5.27
35	Savings Calculator			4142	5.50
104	Triangle Area	ES		3439	5.82
25	Linear Congruential Generator	RU		4095	5.52
44	Double Dice Roll	RU		3888	5.61
32	Josephus Problem	RU		3986	5.57
81	Bit Count	RU		3487	5.80
19	Matching Brackets	ES RU		3732	5.68
128	Combinations Counting			2732	6.22
58	Card Names			3316	5.89
47	Caesar Shift Cipher	SK		3395	5.85
49	Rock Paper Scissors			3347	5.87
55	Matching Words			3242	5.93
94	Fool's Day 2014	SK		2827	6.16
59	Bulls and Cows			2933	6.10
61	Prime Numbers Generation	RU		2889	6.13
22	Two Printers	ES RU		3102	6.00
42	Blackjack Counting			2665	6.27
120	Selection Sort			2084	6.69
38	Quadratic Equation			2448	6.41
33	Parity Control	RU		2411	6.44
53	King and Queen			2147	6.64
171	Tree Height Measurement			1491	7.27
34	Binary Search			2214	6.59
37	Mortgage Calculator	ZH		2082	6.69
45	Cards Shuffling	ZH		2028	6.74
69	Fibonacci Divisibility			1898	6.86
63	Integer Factorization	ZH		1819	6.93
46	Tic-Tac-Toe	ZH		1874	6.88
72	Funny Words Generator			1626	7.12
62	Prime Ranges			1661	7.09
121	Insertion Sort			1381	7.41
75	Yacht or Dice Poker			1541	7.22
172	Cloud Altitude Measurement			1119	7.77
127	Anagrams			1295	7.52
134	Flying Text Screensaver			1199	7.65
39	Share Price Volatility			1553	7.20
156	Luhn Algorithm	SK		1019	7.93
114	Tricky Printing			1140	7.74
80	Duel Chances			1162	7.71
428	Broken Keyboard			47	13.24
135	Variable Length Code			917	8.12
36	Code Guesser	UA		1208	7.64
74	Clock Hands			1093	7.81
105	Convex Polygon Area			944	8.07
54	Pythagorean Triples			1065	7.86
145	Modular Exponentiation			790	8.38
73	Hexagonal Grid			963	8.03
116	Summing Up			829	8.29
442	Chomp			4	17.17
97	Girls and Pigs			863	8.22
187	Static Web Page			595	8.87
181	Reverse Polish Notation			606	8.84
188	Basics of HTML			569	8.95
122	QuickSort			699	8.59
98	Azimuth at Treasure Island			749	8.47
437	Elections and Happiness			14	15.26
85	Rotation in 2D Space			756	8.45
51	Dungeons and Dragons Dice	UA		817	8.32
56	Life is Simple			790	8.38
429	Moving Average in Time			29	14.06
40	Paths in the Grid	UA		805	8.34
70	Most Frequent Word			722	8.53
66	Caesar Cipher Cracker			722	8.53
88	Pitch and Notes			667	8.67
433	A Crime on Logic Island		csfpython	19	14.77
108	Star Medals			606	8.84
440	Mud Walker			6	16.59
87	Tree Builder			610	8.83
95	Simple Linear Regression			596	8.87
60	Sweet Harvest			646	8.73
77	Point to Segment Distance			603	8.85
211	Information Entropy			380	9.65
86	Brainfuck Interpreter			567	8.95
207	Suffix Array			375	9.67
425	Explosive Breeding			28	14.12
176	Say 100			407	9.53
91	Game of 2048			530	9.07
71	Fibonacci Divisibility Advanced			557	8.98
143	Extended Euclidean Algorithm			440	9.39
101	Gradient Calculation			492	9.20
195	Mul Two			354	9.77
119	Brain Fibo			461	9.31
191	Spaceship Weight Fraud			352	9.78
82	Levenshtein Distance			500	9.17
206	Base-32 Encoding			319	9.95
438	Maze Generator			7	16.36
89	Instrument Tuner			467	9.29
64	Maze Pathfinder			488	9.21
131	Four Pics One Word			392	9.59
385	Number of steps in Euclidean Algorithm		gardengnome	73	12.49
436	Avoid the Grid Points		csfpython	9	15.97
79	Cycles Detection			445	9.37
434	A Crime on Logic Island Advanced		csfpython	11	15.65
92	Binary Heap			420	9.47
377	Sum of Digits Divisibility			79	12.36
189	Dynamic Web Page			302	10.04
150	Introducing Regexps			333	9.87
126	Sequence of Squares			359	9.74
136	Variable Length Code Unpack			347	9.80
83	Graph Generator			405	9.54
167	Copy Line			298	10.07
90	Lexicographic Permutations			381	9.64
170	Binary Search in Array			294	10.09
301	Skyscraper Price			152	11.23
197	Loops in Assembly			261	10.30
78	Bezier Curves			385	9.62
154	Breadth First Search			302	10.04
117	Divide by Two			327	9.91
435	Maze Mapping API-Robot			8	16.15
443	Football League Tables		csfpython	-	19.97
65	Transitive Closure on Candy States			374	9.67
99	Uphill Shooting			340	9.84
144	Modular Inverse			277	10.19
155	Depth First Search			264	10.28
174	Calculation of Pi			243	10.42
161	Topological Sorting			251	10.36
133	Billiard Ball			268	10.25
165	Safe Landing			236	10.47
140	Proper Bracket Sequences			254	10.34
427	Cheapest Bus Tickets			13	15.38
76	Pawn Move Validator			299	10.06
96	Snake Arcade			280	10.17
190	Query String Parameters			204	10.72
439	Power Sum of Digits		csfpython	3	17.56
184	Matches Picking		quandray	206	10.71
366	Image Cutting		oezguery	60	12.83
123	Knapsack of Integers			248	10.38
103	Easter Eggs			263	10.28
93	Starving Priority Queue			269	10.24
84	Dijkstra in the Network			271	10.23
130	Combinations with Repetitions			233	10.49
125	Bogosort			234	10.48
173	Chords of Music			197	10.78
399	Methane Identification		moxieman	31	13.95
323	Next Palindrome		csfpython	85	12.23
371	Pages to Print			50	13.14
109	Lucky Tickets			229	10.52
146	Color Cubes			202	10.74
151	Word Ladders			195	10.80
441	Max versus Min		csfpython	1	18.77
360	Whisky Blending		csfpython	54	13.01
208	Neighborhood of a String			150	11.25
129	Enumerating Combinations			200	10.76
414	MIDI Variable Length Numbers			18	14.85
164	Page Rank			175	10.99
138	Huffman Coding			188	10.86
418	Expected Number of Random Moves		moxieman	15	15.15
139	Beam Balance and Masses			186	10.88
194	Convex Hull and Farmers			148	11.28
337	Introducing Zeckendorf		csfpython	62	12.77
201	Point in Polygon			142	11.35
432	Ball Bearing Collisions		csfpython	6	16.59
199	Employees Web App			141	11.36
411	Elo Ratings		moxieman	18	14.85
423	Russian Dolls		csfpython	11	15.65
137	Shannon-Fano Coding			174	11.00
329	Roman Arithmetic		csfpython	64	12.72
152	RSA Cryptography			164	11.10
192	Gangster Battles			140	11.37
374	Longest Common Subsequence			38	13.61
368	Number Base Palindrome		csfpython	41	13.48
111	Necklace Count			178	10.96
244	Introducing SQL			105	11.87
110	Lucky Tickets Advanced			168	11.06
168	Caesar meets BF			137	11.41
245	Aggregations in SQL			95	12.04
253	Beautiful Line Chart			91	12.11
269	Fibonacci coding			83	12.27
421	Princess and Tiger			10	15.80
372	String Minimization			33	13.84
148	Public Key Cryptography Intro			138	11.40
401	Methane Rotation		moxieman	19	14.77
202	Dancing Pairs			111	11.77
364	Arthur Engel's Randomizer			36	13.70
431	King and Rook Checkmate			5	16.86
162	Rubik's Cube			129	11.51
179	Look and Say binary			121	11.62
124	Knapsack Backtracking			146	11.30
359	Find 3 Numbers		csfpython	38	13.61
420	Life on a String		csfpython	10	15.80
106	Random Search Optimization			152	11.23
198	Prn Hex Str			110	11.79
214	Sick Travellers			102	11.92
182	Frodo and Black Riders			114	11.73
400	Memory Check			18	14.85
177	Nim Game			113	11.74
160	Social Web Scraper			119	11.65
185	Simple 3D Scene			108	11.82
294	Vigenere Cipher			62	12.77
102	Travelling Salesman			141	11.36
407	River Labyrinth			14	15.26
157	Emirp primE			115	11.71
246	Joins in SQL			79	12.36
158	Hamming Codes			114	11.73
384	Equal Hamming Distance		csfpython	23	14.45
426	Weighted Sum of Digits 2		csfpython	6	16.59
159	Hard Life			105	11.87
258	Text Justification			67	12.64
381	Finding Squares		csfpython	22	14.52
265	Update in SQL			63	12.74
196	Fibonacci Randomizer			86	12.21
153	Fermat goes hacking RSA			100	11.95
291	Squirrels vs. Acorns		zelevin	52	13.07
412	Json Fix			10	15.80
277	The Adventure of Morse Code		zelevin	56	12.95
100	Crossing the Road			116	11.70
281	Basic Tokenizer			54	13.01
115	Gradient Descent for SLE			110	11.79
141	Sliding Window Search			99	11.97
186	Simple 3D Scene (cont)			84	12.25
406	Wormholes of Cygnus		moxieman	11	15.65
193	Maximum Flow			77	12.40
166	Page Rank as Eigenvector			85	12.23
209	Suffix Array Advanced			71	12.54
210	Ticket Puzzle			70	12.56
142	LZ77 decompression			90	12.13
390	Card Pairing Solitaire			15	15.15
219	Neural Network Calculation			65	12.69
203	Tic-Tac-Toe Minimax Algorithm			69	12.59
112	Travelling Salesman Inverted			94	12.06
430	Cutting Paper		csfpython	3	17.56
409	Election Fever		csfpython	9	15.97
113	Ground Zero			93	12.08
405	Three Friendly Knights		csfpython	10	15.80
216	Cracking Linear Congruential Generator			63	12.74
351	Nicomachus			25	14.31
274	Two Buckets			45	13.32
403	Hi-Lo dice game			10	15.80
335	Venus Visible			28	14.12
132	Stream Cipher Breaking			82	12.29
163	Colliding Balls			72	12.52
389	Binary Split Guessing Game		csfpython	13	15.38
175	Algae Robot			67	12.64
408	Mad Beaver in River Labyrinth			8	16.15
259	Easter Bunnies		gardengnome	45	13.32
205	Clustering the Stars			58	12.89
107	Knight's Tour			82	12.29
293	Sums of Triplets			35	13.74
230	Move-To-Front Transform			50	13.14
200	Fizz Buzz in Asm			57	12.92
334	Find all of the SETs		csfpython	25	14.31
204	Wandering Star			55	12.98
315	Count the Common Factors		csfpython	29	14.06
241	Village Ways			46	13.28
413	Tree Painting		csfpython	6	16.59
376	Cartesian Tree Visualization			14	15.26
212	BCD to Hex			50	13.14
292	Factorial Trailing Zeroes			32	13.90
218	Rain Must Fall	DE		48	13.21
393	Urban Planning		csfpython	10	15.80
416	Socket Server		testuser	5	16.86
388	Fibonacci Guessing Game			11	15.65
257	Missing Records in SQL			39	13.56
149	Prime Chains			61	12.80
233	Language Study			42	13.44
379	Dice with Infinity Sides		telebashna	12	15.51
307	The Problem of Too Many Clues		zelevin	26	14.24
398	Collecting Diamonds		csfpython	8	16.15
178	Maze of the Wumpus			51	13.11
147	Color Cubes Advanced			57	12.92
330	Easter Bunnies Are Back		gardengnome	21	14.60
392	Fixing an Anagram			9	15.97
118	Maxit Single-Player			61	12.80
386	Advent Calendar Chocolate		gardengnome	10	15.80
180	Simple Game of Sticks			48	13.21
223	Introducing Scheme			40	13.52
417	Unfortunate Bubble Sort		gardengnome	4	17.17
352	Hurkle			16	15.05
395	Growth of Micro-Organisms		csfpython	8	16.15
347	Unwanted Multiples		csfpython	16	15.05
324	Merge Sort			20	14.68
375	Space Invaders			11	15.65
363	Language Detector			13	15.38
415	Smallest Message		gardengnome	4	17.17
229	Burrows-Wheeler Transform			36	13.70
297	Collatz in the Range			24	14.38
338	Throwing Easter Eggs		gardengnome	17	14.95
255	LCM of a range			31	13.95
367	Roguelike 1d			12	15.51
354	Too Many Divisors		csfpython	14	15.26
299	Tree Visualizer			23	14.45
353	Hurkle Hunter			14	15.26
183	Connect Four			42	13.44
247	Towers of Hanoi			31	13.95
296	Tree Value	RU	csfpython	23	14.45
382	Die Throw Sequences		csfpython	9	15.97
419	Special Digits		csfpython	3	17.56
349	Burrows		gardengnome	14	15.26
346	Long Decimal Fractions		csfpython	14	15.26
287	Palindrome Frog		csfpython	23	14.45
358	Mandelbrot Set			12	15.51
331	Rotating Toy Display		csfpython	16	15.05
284	Rotate Array In-Place			23	14.45
424	New Towers of Hanoi		csfpython	2	18.06
404	Methane Normalization		moxieman	5	16.86
357	Ulam's Prime Spiral			12	15.51
290	Every Leaf on Every Tree		zelevin	22	14.52
383	E2C2S - try harder!		gardengnome	8	16.15
340	Zeckendorf Lite		csfpython	14	15.26
298	Revoltle		zelevin	20	14.68
270	Hexlife			24	14.38
339	Parking Lot			14	15.26
217	Personality Swap			31	13.95
238	Bear Hunt			28	14.12
249	Turing Increment			26	14.24
256	Rook Jump Maze			25	14.31
261	Easter Bunnies 2D		gardengnome	24	14.38
422	Mabinogion Sheep		moxieman	2	18.06
312	The Shredder Conundrum		zelevin	17	14.95
243	Grille Encryption			26	14.24
362	Euclid, Manhattan and Chebyshev			10	15.80
234	Train Merge			27	14.18
286	Self-Printing Program			20	14.68
361	Rogue Mazes			10	15.80
313	Seven Segment Decoder			16	15.05
282	Predictable Board Game		csfpython	20	14.68
169	Automated Landing			34	13.79
268	Logic Transformation			21	14.60
300	Run-Length Encoding			17	14.95
387	Big Numbers		csfpython	6	16.59
344	Throwing Easter Eggs Part 2		gardengnome	11	15.65
285	Rotate Matrix In Place			18	14.85
402	Game of Stones		csfpython	4	17.17
275	Three Buckets			19	14.77
410	Village Door Shuffle		csfpython	3	17.56
250	Turing Clone			21	14.60
326	Sum Them Forth			12	15.51
271	A Knight some Trolls and a Princess		csfpython	18	14.85
213	Micro-Life	SK		24	14.38
314	The Sorites Solution		zelevin	13	15.38
332	Easter Bunnies 2D Are Back		gardengnome	11	15.65
341	Zeckendorf Advanced		csfpython	10	15.80
378	Space Invaders Automation			6	16.59
220	Neural Network Training			22	14.52
336	Currency Arbitrage			10	15.80
394	Many Shortest Routes		csfpython	4	17.17
289	The Case of the Desperate Mastermind		zelevin	14	15.26
306	Line Drawing Algorithm			12	15.51
380	Treap Study			5	16.86
316	Apogee			11	15.65
262	Easter Bunnies 2D Advanced		gardengnome	16	15.05
260	Low Cost Road Network		csfpython	16	15.05
303	Towers Under Cover			12	15.51
288	Langton's Ant		csfpython	13	15.38
221	XWords		quandray	19	14.77
254	Rule 30 by Turing			16	15.05
231	Dice Black Jack			18	14.85
343	Village of Ticks			8	16.15
365	Flower Border Arrangements		csfpython	6	16.59
263	Easter Bunnies 3D		gardengnome	15	15.15
319	Tower of Hanoi Rules		csfpython	10	15.80
222	Easter Eggs Advanced			18	14.85
397	Trading Bot			3	17.56
350	Colourful Egg Sequences		gardengnome	7	16.36
266	Pancake Sorting			14	15.26
276	Lucky Pairs		csfpython	13	15.38
396	Chocolate Triangles and BF		moxieman	3	17.56
311	The Mirror Maze		zelevin	10	15.80
309	Board Game Sequences		csfpython	10	15.80
333	Happy Triplets			8	16.15
345	Elliptic Curves Basics			7	16.36
320	Accordion		pearlbarley	9	15.97
295	Vigenere Cipher Cracker			11	15.65
279	Two Buckets Advanced		csfpython	12	15.51
235	Train Merge Advanced			15	15.15
325	Ultimate Sort Trial			8	16.15
391	Scout Proficiency Badges		csfpython	3	17.56
242	Comment Stripper			14	15.26
305	The Catacombs of Chronos		zelevin	9	15.97
328	Beep Beep Beep			7	16.36
267	Turing Maze			11	15.65
237	Road Network Destruction			13	15.38
310	Board Game Sequences Advanced		csfpython	8	16.15
369	Flappy Bird			4	17.17
308	Circle Drawing Algorithm			8	16.15
322	Gray Decoder			7	16.36
227	Hashtable Implementation			13	15.38
304	Ordered Brackets		csfpython	8	16.15
215	Klotski	SK		13	15.38
327	Dobbin's Long Journey		csfpython	6	16.59
342	Adaptive Arithmetic Coding			5	16.86
252	Shadok and Gibis			10	15.80
373	Railroad Rat		csfpython	3	17.56
355	Robots Game			4	17.17
264	Party Presents		csfpython	9	15.97
226	Multiplicative Persistence Backtrace			11	15.65
225	Hamurabi			11	15.65
224	Transposing List of Lists			11	15.65
370	Jewels			3	17.56
248	Christmas Puzzle			9	15.97
283	Predictable Board Game on 10 Boards		csfpython	7	16.36
302	Sound-Controlled Robot			6	16.59
278	Polyomino Generation			7	16.36
251	Radio Spies			8	16.15
356	Robots Game Autoplay			3	17.56
239	Foxes and Geese			8	16.15
236	Is the Earth Flat			8	16.15
280	Three Buckets Re-visited		csfpython	6	16.59
348	Trick-Taking Game			3	17.56
273	Logic Glitches			6	16.59
272	Hexplore			6	16.59
321	Hanoi Tower Heights		csfpython	4	17.17
317	Launch to Orbit			4	17.17
240	Playfair Cipher Cracking			7	16.36
232	Shift Register Randomizer			7	16.36
228	Maze Mapping Robot			6	16.59
318	Launch to Orbit automated			2	18.06