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		59381	1.00
2	Sum in Loop	DE ES FR AR ZH RO RU SK		36001	1.87
3	Sums in Loop	DE ES FR AR ZH RO RU SK		27444	2.34
4	Minimum of Two	DE ES FR AR ZH RO RU SK		23922	2.58
5	Minimum of Three	DE ES FR AR ZH RO RU SK		21419	2.77
15	Maximum of array	DE ES AR ZH RO RU SK		18724	3.00
6	Rounding	DE ES AR ZH RO RU SK		17163	3.16
7	Fahrenheit to Celsius	DE ES AR ZH RO RU SK		16444	3.23
20	Vowel Count	DE ES AR ZH RO RU SK		13350	3.59
11	Sum of digits	DE ES RU ZH SK		13282	3.60
8	Arithmetic Progression	DE ES RU ZH SK		12478	3.71
41	Median of Three	DE ES AR ZH RO RU SK		11429	3.86
9	Triangles	DE ES RU ZH SK		11925	3.79
28	Body Mass Index	DE ES ZH RU SK		11297	3.88
13	Weighted sum of digits	DE ES RU ZH SK		10784	3.96
43	Dice Rolling	DE ES ZH RU SK		9705	4.15
16	Average of an array	DE ES RU SK		10223	4.06
30	Reverse String	DE ES RU SK		9655	4.16
17	Array Checksum	DE ES RU SK		9499	4.18
21	Array Counters	DE ES RU SK		8841	4.31
10	Linear Function	DE ES RU SK		8594	4.36
48	Collatz Sequence	DE ES RU SK		7666	4.56
12	Modulo and time difference	DE ES RU SK		7801	4.53
14	Modular Calculator	ES SK		7216	4.66
27	Bubble Sort	ES RU SK		6544	4.83
26	Greatest Common Divisor	ES SK RU		6369	4.88
18	Square Root	ES RU		6193	4.93
29	Sort with Indexes	RU		5906	5.01
50	Palindromes	DE ES RU SK		5452	5.15
23	Bubble in Array	ES RU		5654	5.08
52	Pythagorean Theorem	RU		5243	5.22
31	Rotate String	ES RU		5419	5.16
67	Fibonacci Sequence	RU		4698	5.41
68	Bicycle Race	ES RU		4664	5.42
24	Neumann's Random Generator	DE ES RU		5053	5.28
57	Smoothing the Weather	ES RU		4650	5.42
35	Savings Calculator			4478	5.49
104	Triangle Area	ES		3737	5.80
25	Linear Congruential Generator	RU		4409	5.52
32	Josephus Problem	RU		4292	5.56
44	Double Dice Roll	RU		4174	5.61
81	Bit Count	RU		3741	5.80
19	Matching Brackets	ES RU		4056	5.66
58	Card Names			3572	5.88
49	Rock Paper Scissors			3630	5.85
47	Caesar Shift Cipher	SK		3633	5.85
128	Combinations Counting			2938	6.22
55	Matching Words			3493	5.92
94	Fool's Day 2014	SK		3048	6.16
59	Bulls and Cows			3162	6.09
61	Prime Numbers Generation	RU		3099	6.13
22	Two Printers	ES RU		3366	5.99
42	Blackjack Counting			2881	6.26
120	Selection Sort			2279	6.66
38	Quadratic Equation			2669	6.39
33	Parity Control	RU		2597	6.44
53	King and Queen			2325	6.63
34	Binary Search			2412	6.56
171	Tree Height Measurement			1614	7.26
37	Mortgage Calculator	ZH		2250	6.69
45	Cards Shuffling	ZH		2201	6.72
69	Fibonacci Divisibility			2041	6.85
63	Integer Factorization	ZH		1959	6.93
46	Tic-Tac-Toe	ZH		2020	6.87
62	Prime Ranges			1795	7.08
72	Funny Words Generator			1736	7.14
121	Insertion Sort			1518	7.37
75	Yacht or Dice Poker			1645	7.23
172	Cloud Altitude Measurement			1215	7.75
127	Anagrams			1354	7.57
39	Share Price Volatility			1677	7.20
134	Flying Text Screensaver			1250	7.71
156	Luhn Algorithm	SK		1097	7.93
114	Tricky Printing			1182	7.80
80	Duel Chances			1248	7.71
36	Code Guesser	UA		1341	7.58
74	Clock Hands			1172	7.82
135	Variable Length Code			985	8.12
54	Pythagorean Triples			1160	7.84
105	Convex Polygon Area			1016	8.07
73	Hexagonal Grid			1046	8.01
145	Modular Exponentiation			857	8.36
97	Girls and Pigs			935	8.21
116	Summing Up			860	8.35
181	Reverse Polish Notation			660	8.81
98	Azimuth at Treasure Island			812	8.45
51	Dungeons and Dragons Dice	UA		891	8.29
122	QuickSort			748	8.60
495	Counting Arithmetic Progressions		csfpython	1	18.89
85	Rotation in 2D Space			819	8.44
187	Static Web Page			611	8.95
40	Paths in the Grid	UA		902	8.27
56	Life is Simple			852	8.37
188	Basics of HTML			582	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			645	8.85
77	Point to Segment Distance			656	8.82
494	Holiday Travel		csfpython	2	18.19
86	Brainfuck Interpreter			599	8.98
211	Information Entropy			412	9.63
428	Broken Keyboard			97	12.13
71	Fibonacci Divisibility Advanced			610	8.95
91	Game of 2048			576	9.05
207	Suffix Array			400	9.68
480	Coin Payments		csfpython	21	14.72
101	Gradient Calculation			534	9.18
143	Extended Euclidean Algorithm			470	9.40
176	Say 100			424	9.58
82	Levenshtein Distance			543	9.15
485	Magic 3		csfpython	13	15.51
191	Spaceship Weight Fraud			386	9.74
119	Brain Fibo			472	9.40
89	Instrument Tuner			508	9.27
206	Base-32 Encoding			357	9.88
64	Maze Pathfinder			531	9.19
195	Mul Two			369	9.82
79	Cycles Detection			496	9.31
92	Binary Heap			464	9.42
131	Four Pics One Word			406	9.66
487	Reduce and Equalise		csfpython	9	16.09
83	Graph Generator			454	9.46
476	Prime Vowel Count		csfpython	21	14.72
154	Breadth First Search			356	9.88
301	Skyscraper Price			200	10.88
136	Variable Length Code Unpack			368	9.83
90	Lexicographic Permutations			410	9.64
78	Bezier Curves			422	9.59
150	Introducing Regexps			345	9.94
189	Dynamic Web Page			305	10.15
126	Sequence of Squares			366	9.84
65	Transitive Closure on Candy States			420	9.60
385	Number of steps in Euclidean Algorithm		gardengnome	104	12.01
167	Copy Line			310	10.12
170	Binary Search in Array			305	10.15
99	Uphill Shooting			361	9.86
197	Loops in Assembly			269	10.37
161	Topological Sorting			297	10.20
117	Divide by Two			336	9.98
461	Lucky 7		csfpython	30	14.13
144	Modular Inverse			302	10.17
377	Sum of Digits Divisibility			100	12.08
155	Depth First Search			288	10.25
429	Moving Average in Time			55	13.10
174	Calculation of Pi			260	10.43
76	Pawn Move Validator			338	9.97
481	Field Trip		csfpython	11	15.78
93	Starving Priority Queue			317	10.08
425	Explosive Breeding			55	13.10
133	Billiard Ball			283	10.28
96	Snake Arcade			305	10.15
140	Proper Bracket Sequences			271	10.36
165	Safe Landing			251	10.49
492	Fastest Clearance		csfpython	2	18.19
484	A Message from Deep Space		csfpython	8	16.28
103	Easter Eggs			283	10.28
123	Knapsack of Integers			267	10.38
184	Matches Picking		quandray	223	10.69
84	Dijkstra in the Network			291	10.23
173	Chords of Music			220	10.72
130	Combinations with Repetitions			248	10.51
471	Missing Digits		csfpython	16	15.17
190	Query String Parameters			207	10.82
444	White Rectangle			34	13.92
493	Ternary Logic			1	18.89
472	Unreachable Amounts		csfpython	15	15.28
125	Bogosort			246	10.52
109	Lucky Tickets			254	10.47
146	Color Cubes			214	10.76
323	Next Palindrome		csfpython	105	11.99
366	Image Cutting		oezguery	78	12.50
129	Enumerating Combinations			221	10.71
491	Lucky Number Scores		csfpython	2	18.19
151	Word Ladders			201	10.87
371	Pages to Print			72	12.64
164	Page Rank			191	10.96
139	Beam Balance and Masses			204	10.85
208	Neighborhood of a String			164	11.22
482	SS Numbers		csfpython	7	16.48
489	TV Charity Fundraiser		csfpython	3	17.69
253	Beautiful Line Chart			135	11.56
138	Huffman Coding			199	10.89
374	Longest Common Subsequence			67	12.76
478	Robot Deliveries		csfpython	9	16.09
194	Convex Hull and Farmers			164	11.22
360	Whisky Blending		csfpython	73	12.62
437	Elections and Happiness			31	14.07
468	The Garden of Words		zelevin	14	15.39
201	Point in Polygon			157	11.30
152	RSA Cryptography			179	11.07
137	Shannon-Fano Coding			184	11.03
111	Necklace Count			197	10.91
337	Introducing Zeckendorf		csfpython	80	12.46
433	A Crime on Logic Island		csfpython	31	14.07
102	Travelling Salesman			198	10.90
490	Circuit Board Connections		csfpython	2	18.19
192	Gangster Battles			148	11.40
399	Methane Identification		moxieman	46	13.41
110	Lucky Tickets Advanced			186	11.01
244	Introducing SQL			121	11.75
199	Employees Web App			142	11.47
329	Roman Arithmetic		csfpython	77	12.53
269	Fibonacci coding			104	12.01
368	Number Base Palindrome		csfpython	57	13.04
148	Public Key Cryptography Intro			152	11.36
106	Random Search Optimization			168	11.18
294	Vigenere Cipher			86	12.34
245	Aggregations in SQL			107	11.96
124	Knapsack Backtracking			158	11.29
168	Caesar meets BF			138	11.52
202	Dancing Pairs			122	11.73
162	Rubik's Cube			138	11.52
214	Sick Travellers			115	11.84
179	Look and Say binary			129	11.64
182	Frodo and Black Riders			122	11.73
198	Prn Hex Str			113	11.87
177	Nim Game			119	11.78
160	Social Web Scraper			125	11.69
488	Accurate Curve Fitting		csfpython	2	18.19
246	Joins in SQL			92	12.22
158	Hamming Codes			124	11.71
477	Lottery Balls		csfpython	6	16.71
466	Dictionary Entries		csfpython	10	15.93
185	Simple 3D Scene			112	11.88
157	Emirp primE			122	11.73
359	Find 3 Numbers		csfpython	48	13.33
258	Text Justification			84	12.38
364	Arthur Engel's Randomizer			46	13.41
414	MIDI Variable Length Numbers			28	14.25
459	Number String Multiples of Thirteen		csfpython	12	15.64
449	Space Pirates		csfpython	15	15.28
463	Crossing Towns		csfpython	10	15.93
475	Medieval Medicine		zelevin	6	16.71
372	String Minimization			40	13.64
159	Hard Life			110	11.91
447	Fixed Product, Minimum Sum		csfpython	15	15.28
401	Methane Rotation		moxieman	30	14.13
153	Fermat goes hacking RSA			110	11.91
100	Crossing the Road			127	11.67
418	Expected Number of Random Moves		moxieman	24	14.50
474	Reachable Amounts		gardengnome	6	16.71
411	Elo Ratings		moxieman	26	14.37
265	Update in SQL			72	12.64
324	Merge Sort			52	13.20
483	Sixes and Sevens		csfpython	3	17.69
115	Gradient Descent for SLE			116	11.82
384	Equal Hamming Distance		csfpython	33	13.97
291	Squirrels vs. Acorns		zelevin	61	12.93
281	Basic Tokenizer			64	12.84
486	Two Colour Special Nim		csfpython	2	18.19
196	Fibonacci Randomizer			89	12.28
141	Sliding Window Search			105	11.99
469	Game of Generals			7	16.48
277	The Adventure of Morse Code		zelevin	63	12.87
186	Simple 3D Scene (cont)			89	12.28
427	Cheapest Bus Tickets			19	14.89
458	Mountain Panorama		csfpython	10	15.93
112	Travelling Salesman Inverted			108	11.94
193	Maximum Flow			85	12.36
210	Ticket Puzzle			80	12.46
166	Page Rank as Eigenvector			92	12.22
142	LZ77 decompression			98	12.11
209	Suffix Array Advanced			79	12.48
460	Carlsdale Caverns		csfpython	9	16.09
452	Implication in Logic			11	15.78
113	Ground Zero			102	12.04
216	Cracking Linear Congruential Generator			73	12.62
203	Tic-Tac-Toe Minimax Algorithm			76	12.55
219	Neural Network Calculation			71	12.67
434	A Crime on Logic Island Advanced		csfpython	15	15.28
274	Two Buckets			56	13.07
464	Graph to Loops Decomposition			7	16.48
400	Memory Check			23	14.57
132	Stream Cipher Breaking			87	12.32
107	Knight's Tour			93	12.20
351	Nicomachus			34	13.92
467	Permutation Generator		csfpython	6	16.71
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
457	Railroad and Hamilton			8	16.28
175	Algae Robot			73	12.62
205	Clustering the Stars			64	12.84
446	Hangman			10	15.93
230	Move-To-Front Transform			57	13.04
473	Skittles		csfpython	4	17.30
293	Sums of Triplets			43	13.52
445	Formula 1			10	15.93
315	Count the Common Factors		csfpython	38	13.73
403	Hi-Lo dice game			19	14.89
407	River Labyrinth			18	14.98
435	Maze Mapping API-Robot			12	15.64
335	Venus Visible			33	13.97
406	Wormholes of Cygnus		moxieman	18	14.98
453	SR latch			8	16.28
218	Rain Must Fall	DE		57	13.04
204	Wandering Star			59	12.98
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
412	Json Fix			15	15.28
438	Maze Generator			10	15.93
390	Card Pairing Solitaire			19	14.89
421	Princess and Tiger			13	15.51
212	BCD to Hex			52	13.20
118	Maxit Single-Player			68	12.74
233	Language Study			47	13.37
307	The Problem of Too Many Clues		zelevin	33	13.97
440	Mud Walker			9	16.09
423	Russian Dolls		csfpython	12	15.64
223	Introducing Scheme			47	13.37
147	Color Cubes Advanced			60	12.95
180	Simple Game of Sticks			54	13.13
450	Bead Games		csfpython	7	16.48
178	Maze of the Wumpus			54	13.13
379	Dice with Infinity Sides		telebashna	19	14.89
247	Towers of Hanoi			41	13.60
442	Chomp			8	16.28
465	Red Blue Hackenbush		csfpython	4	17.30
229	Burrows-Wheeler Transform			42	13.56
376	Cartesian Tree Visualization			18	14.98
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	14.72
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
347	Unwanted Multiples		csfpython	21	14.72
455	D flip-flop			5	16.98
297	Collatz in the Range			28	14.25
338	Throwing Easter Eggs		gardengnome	22	14.65
454	Multiplexer 4x4			5	16.98
270	Hexlife			31	14.07
284	Rotate Array In-Place			29	14.19
354	Too Many Divisors		csfpython	19	14.89
296	Tree Value	RU	csfpython	27	14.31
388	Fibonacci Guessing Game			14	15.39
409	Election Fever		csfpython	11	15.78
349	Burrows		gardengnome	19	14.89
405	Three Friendly Knights		csfpython	11	15.78
290	Every Leaf on Every Tree		zelevin	26	14.37
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
346	Long Decimal Fractions		csfpython	18	14.98
243	Grille Encryption			31	14.07
353	Hurkle Hunter			17	15.07
432	Ball Bearing Collisions		csfpython	7	16.48
312	The Shredder Conundrum		zelevin	22	14.65
256	Rook Jump Maze			29	14.19
392	Fixing an Anagram			12	15.64
287	Palindrome Frog		csfpython	25	14.43
375	Space Invaders			14	15.39
217	Personality Swap			33	13.97
340	Zeckendorf Lite		csfpython	18	14.98
249	Turing Increment			29	14.19
331	Rotating Toy Display		csfpython	19	14.89
298	Revoltle		zelevin	23	14.57
339	Parking Lot			18	14.98
362	Euclid, Manhattan and Chebyshev			15	15.28
261	Easter Bunnies 2D		gardengnome	27	14.31
268	Logic Transformation			26	14.37
462	Rota Boards		csfpython	3	17.69
479	Robot and the Wall			1	18.89
300	Run-Length Encoding			22	14.65
393	Urban Planning		csfpython	11	15.78
169	Automated Landing			37	13.78
470	Shogi Engine			2	18.19
417	Unfortunate Bubble Sort		gardengnome	8	16.28
408	Mad Beaver in River Labyrinth			9	16.09
363	Language Detector			14	15.39
415	Smallest Message		gardengnome	8	16.28
295	Vigenere Cipher Cracker			21	14.72
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
431	King and Rook Checkmate			6	16.71
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
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	16.09
250	Turing Clone			24	14.50
358	Mandelbrot Set			13	15.51
456	Every Third Bit			3	17.69
386	Advent Calendar Chocolate		gardengnome	10	15.93
344	Throwing Easter Eggs Part 2		gardengnome	14	15.39
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
441	Max versus Min		csfpython	4	17.30
419	Special Digits		csfpython	6	16.71
341	Zeckendorf Advanced		csfpython	13	15.51
260	Low Cost Road Network		csfpython	20	14.81
213	Micro-Life	SK		24	14.50
416	Socket Server		testuser	6	16.71
220	Neural Network Training			23	14.57
332	Easter Bunnies 2D Are Back		gardengnome	13	15.51
402	Game of Stones		csfpython	7	16.48
413	Tree Painting		csfpython	6	16.71
222	Easter Eggs Advanced			22	14.65
448	Button Cycles		csfpython	3	17.69
266	Pancake Sorting			18	14.98
387	Big Numbers		csfpython	8	16.28
289	The Case of the Desperate Mastermind		zelevin	16	15.17
263	Easter Bunnies 3D		gardengnome	18	14.98
410	Village Door Shuffle		csfpython	6	16.71
336	Currency Arbitrage			12	15.64
262	Easter Bunnies 2D Advanced		gardengnome	18	14.98
422	Mabinogion Sheep		moxieman	5	16.98
221	XWords		quandray	21	14.72
254	Rule 30 by Turing			18	14.98
343	Village of Ticks			11	15.78
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
404	Methane Normalization		moxieman	6	16.71
430	Cutting Paper		csfpython	4	17.30
311	The Mirror Maze		zelevin	13	15.51
350	Colourful Egg Sequences		gardengnome	10	15.93
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
316	Apogee			12	15.64
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
345	Elliptic Curves Basics			9	16.09
224	Transposing List of Lists			17	15.07
237	Road Network Destruction			16	15.17
267	Turing Maze			14	15.39
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
378	Space Invaders Automation			6	16.71
327	Dobbin's Long Journey		csfpython	9	16.09
310	Board Game Sequences Advanced		csfpython	10	15.93
325	Ultimate Sort Trial			9	16.09
342	Adaptive Arithmetic Coding			8	16.28
322	Gray Decoder			9	16.09
321	Hanoi Tower Heights		csfpython	9	16.09
373	Railroad Rat		csfpython	6	16.71
225	Hamurabi			14	15.39
328	Beep Beep Beep			8	16.28
252	Shadok and Gibis			12	15.64
308	Circle Drawing Algorithm			9	16.09
283	Predictable Board Game on 10 Boards		csfpython	10	15.93
302	Sound-Controlled Robot			9	16.09
278	Polyomino Generation			10	15.93
215	Klotski	SK		13	15.51
251	Radio Spies			11	15.78
370	Jewels			5	16.98
369	Flappy Bird			5	16.98
280	Three Buckets Re-visited		csfpython	9	16.09
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	16.09
396	Chocolate Triangles and BF		moxieman	3	17.69
240	Playfair Cipher Cracking			9	16.09
239	Foxes and Geese			9	16.09
236	Is the Earth Flat			9	16.09
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