Problems

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Volume:

Simple Implementation Algorithms Puzzles Special

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Id	Title	Translations	Author	Solved	Blessing
1	Sum "A+B"	DE ES FR AR ZH RO RU SK		56346	1.00
2	Sum in Loop	DE ES FR AR ZH RO RU SK		34319	1.86
3	Sums in Loop	DE ES FR AR ZH RO RU SK		26131	2.33
4	Minimum of Two	DE ES FR AR ZH RO RU SK		22751	2.58
5	Minimum of Three	DE ES FR AR ZH RO RU SK		20382	2.77
15	Maximum of array	DE ES AR ZH RO RU SK		17806	3.00
6	Rounding	DE ES AR ZH RO RU SK		16373	3.15
7	Fahrenheit to Celsius	DE ES AR ZH RO RU SK		15672	3.22
20	Vowel Count	DE ES AR ZH RO RU SK		12710	3.59
11	Sum of digits	DE ES RU ZH SK		12616	3.60
8	Arithmetic Progression	DE ES RU ZH SK		11802	3.72
41	Median of Three	DE ES AR ZH RO RU SK		10829	3.86
9	Triangles	DE ES RU ZH SK		11199	3.81
28	Body Mass Index	DE ES ZH RU SK		10696	3.89
13	Weighted sum of digits	DE ES RU ZH SK		10191	3.97
43	Dice Rolling	DE ES ZH RU SK		9178	4.15
16	Average of an array	DE ES RU SK		9644	4.07
30	Reverse String	DE ES RU SK		9084	4.17
17	Array Checksum	DE ES RU SK		8934	4.20
21	Array Counters	DE ES RU SK		8321	4.32
10	Linear Function	DE ES RU SK		8044	4.38
48	Collatz Sequence	DE ES RU SK		7263	4.56
12	Modulo and time difference	DE ES RU SK		7388	4.53
14	Modular Calculator	ES SK		6830	4.67
27	Bubble Sort	ES RU SK		6173	4.84
26	Greatest Common Divisor	ES SK RU		6013	4.89
18	Square Root	ES RU		5803	4.95
29	Sort with Indexes	RU		5569	5.02
50	Palindromes	DE ES RU SK		5114	5.17
23	Bubble in Array	ES RU		5343	5.09
52	Pythagorean Theorem	RU		4905	5.24
31	Rotate String	ES RU		5100	5.17
67	Fibonacci Sequence	RU		4415	5.42
68	Bicycle Race	ES RU		4389	5.43
57	Smoothing the Weather	ES RU		4416	5.42
24	Neumann's Random Generator	DE ES RU		4772	5.29
35	Savings Calculator			4190	5.51
104	Triangle Area	ES		3486	5.83
25	Linear Congruential Generator	RU		4139	5.54
44	Double Dice Roll	RU		3927	5.63
32	Josephus Problem	RU		4031	5.58
81	Bit Count	RU		3520	5.82
19	Matching Brackets	ES RU		3781	5.69
58	Card Names			3351	5.90
128	Combinations Counting			2765	6.24
47	Caesar Shift Cipher	SK		3436	5.86
49	Rock Paper Scissors			3383	5.89
55	Matching Words			3281	5.94
94	Fool's Day 2014	SK		2867	6.17
59	Bulls and Cows			2966	6.11
61	Prime Numbers Generation	RU		2921	6.14
22	Two Printers	ES RU		3148	6.01
42	Blackjack Counting			2698	6.28
120	Selection Sort			2116	6.70
38	Quadratic Equation			2486	6.42
33	Parity Control	RU		2443	6.45
53	King and Queen			2180	6.65
34	Binary Search			2249	6.59
171	Tree Height Measurement			1516	7.28
37	Mortgage Calculator	ZH		2115	6.70
45	Cards Shuffling	ZH		2060	6.75
69	Fibonacci Divisibility			1929	6.86
63	Integer Factorization	ZH		1846	6.94
46	Tic-Tac-Toe	ZH		1903	6.88
72	Funny Words Generator			1648	7.13
62	Prime Ranges			1687	7.09
121	Insertion Sort			1407	7.41
75	Yacht or Dice Poker			1567	7.22
458	Mountain Panorama		csfpython	3	17.60
172	Cloud Altitude Measurement			1146	7.77
127	Anagrams			1310	7.53
39	Share Price Volatility			1573	7.22
134	Flying Text Screensaver			1211	7.67
156	Luhn Algorithm	SK		1041	7.93
114	Tricky Printing			1149	7.76
80	Duel Chances			1180	7.71
457	Railroad and Hamilton			5	16.89
36	Code Guesser	UA		1229	7.64
135	Variable Length Code			935	8.12
74	Clock Hands			1108	7.82
105	Convex Polygon Area			964	8.07
54	Pythagorean Triples			1080	7.87
145	Modular Exponentiation			810	8.37
73	Hexagonal Grid			988	8.02
116	Summing Up			838	8.31
97	Girls and Pigs			879	8.23
181	Reverse Polish Notation			622	8.83
187	Static Web Page			599	8.89
98	Azimuth at Treasure Island			767	8.46
188	Basics of HTML			573	8.97
122	QuickSort			708	8.60
85	Rotation in 2D Space			774	8.45
51	Dungeons and Dragons Dice	UA		826	8.33
428	Broken Keyboard			61	12.83
56	Life is Simple			801	8.39
40	Paths in the Grid	UA		823	8.34
70	Most Frequent Word			730	8.55
66	Caesar Cipher Cracker			732	8.54
88	Pitch and Notes			677	8.68
108	Star Medals			610	8.86
95	Simple Linear Regression			605	8.87
87	Tree Builder			618	8.84
60	Sweet Harvest			656	8.73
77	Point to Segment Distance			613	8.85
211	Information Entropy			387	9.65
86	Brainfuck Interpreter			576	8.96
207	Suffix Array			378	9.69
91	Game of 2048			540	9.07
71	Fibonacci Divisibility Advanced			567	8.99
176	Say 100			410	9.55
143	Extended Euclidean Algorithm			447	9.40
101	Gradient Calculation			500	9.20
119	Brain Fibo			463	9.34
195	Mul Two			358	9.78
82	Levenshtein Distance			508	9.18
191	Spaceship Weight Fraud			359	9.78
206	Base-32 Encoding			325	9.95
89	Instrument Tuner			474	9.30
429	Moving Average in Time			37	13.68
64	Maze Pathfinder			496	9.22
455	D flip-flop			4	17.21
131	Four Pics One Word			396	9.61
79	Cycles Detection			458	9.36
454	Multiplexer 4x4			5	16.89
444	White Rectangle			17	14.98
92	Binary Heap			428	9.47
452	Implication in Logic			7	16.39
189	Dynamic Web Page			302	10.08
83	Graph Generator			413	9.54
136	Variable Length Code Unpack			353	9.81
385	Number of steps in Euclidean Algorithm		gardengnome	80	12.37
150	Introducing Regexps			334	9.90
126	Sequence of Squares			360	9.77
90	Lexicographic Permutations			388	9.64
170	Binary Search in Array			298	10.10
167	Copy Line			301	10.08
78	Bezier Curves			393	9.62
301	Skyscraper Price			162	11.15
425	Explosive Breeding			34	13.83
197	Loops in Assembly			265	10.30
154	Breadth First Search			307	10.05
456	Every Third Bit			2	18.09
377	Sum of Digits Divisibility			81	12.35
65	Transitive Closure on Candy States			381	9.68
117	Divide by Two			328	9.93
99	Uphill Shooting			344	9.85
144	Modular Inverse			280	10.21
155	Depth First Search			268	10.28
161	Topological Sorting			260	10.34
174	Calculation of Pi			246	10.43
437	Elections and Happiness			18	14.89
133	Billiard Ball			271	10.27
447	Fixed Product, Minimum Sum		csfpython	9	16.00
453	SR latch			4	17.21
165	Safe Landing			242	10.46
140	Proper Bracket Sequences			259	10.34
76	Pawn Move Validator			311	10.03
433	A Crime on Logic Island		csfpython	20	14.71
449	Space Pirates		csfpython	7	16.39
96	Snake Arcade			285	10.18
190	Query String Parameters			204	10.76
184	Matches Picking		quandray	208	10.72
123	Knapsack of Integers			252	10.39
103	Easter Eggs			267	10.29
93	Starving Priority Queue			274	10.25
84	Dijkstra in the Network			277	10.23
130	Combinations with Repetitions			239	10.48
125	Bogosort			237	10.50
173	Chords of Music			201	10.78
446	Hangman			8	16.19
366	Image Cutting		oezguery	63	12.78
109	Lucky Tickets			231	10.54
323	Next Palindrome		csfpython	89	12.19
146	Color Cubes			205	10.75
151	Word Ladders			198	10.81
371	Pages to Print			55	13.01
129	Enumerating Combinations			203	10.76
399	Methane Identification		moxieman	36	13.73
164	Page Rank			180	10.97
208	Neighborhood of a String			153	11.25
360	Whisky Blending		csfpython	59	12.89
138	Huffman Coding			191	10.87
139	Beam Balance and Masses			190	10.88
201	Point in Polygon			148	11.31
194	Convex Hull and Farmers			152	11.26
137	Shannon-Fano Coding			176	11.01
199	Employees Web App			141	11.39
152	RSA Cryptography			166	11.11
337	Introducing Zeckendorf		csfpython	64	12.75
192	Gangster Battles			141	11.39
111	Necklace Count			181	10.96
244	Introducing SQL			109	11.84
329	Roman Arithmetic		csfpython	64	12.75
435	Maze Mapping API-Robot			11	15.69
451	Maximize Toy Production		csfpython	3	17.60
110	Lucky Tickets Advanced			171	11.06
368	Number Base Palindrome		csfpython	43	13.43
434	A Crime on Logic Island Advanced		csfpython	11	15.69
411	Elo Ratings		moxieman	22	14.56
438	Maze Generator			9	16.00
168	Caesar meets BF			137	11.44
440	Mud Walker			8	16.19
253	Beautiful Line Chart			96	12.06
374	Longest Common Subsequence			39	13.60
245	Aggregations in SQL			97	12.04
148	Public Key Cryptography Intro			140	11.41
269	Fibonacci coding			85	12.27
124	Knapsack Backtracking			149	11.30
450	Bead Games		csfpython	3	17.60
162	Rubik's Cube			131	11.52
106	Random Search Optimization			155	11.23
202	Dancing Pairs			112	11.79
179	Look and Say binary			122	11.64
427	Cheapest Bus Tickets			13	15.42
436	Avoid the Grid Points		csfpython	9	16.00
198	Prn Hex Str			111	11.81
445	Formula 1			5	16.89
182	Frodo and Black Riders			117	11.72
214	Sick Travellers			103	11.94
414	MIDI Variable Length Numbers			18	14.89
418	Expected Number of Random Moves		moxieman	16	15.08
102	Travelling Salesman			145	11.35
177	Nim Game			114	11.76
160	Social Web Scraper			120	11.67
372	String Minimization			34	13.83
364	Arthur Engel's Randomizer			37	13.68
294	Vigenere Cipher			65	12.73
185	Simple 3D Scene			108	11.85
158	Hamming Codes			117	11.72
359	Find 3 Numbers		csfpython	38	13.64
246	Joins in SQL			82	12.33
157	Emirp primE			115	11.75
401	Methane Rotation		moxieman	20	14.71
159	Hard Life			106	11.89
258	Text Justification			70	12.60
442	Chomp			5	16.89
400	Memory Check			19	14.80
265	Update in SQL			64	12.75
196	Fibonacci Randomizer			87	12.23
423	Russian Dolls		csfpython	11	15.69
153	Fermat goes hacking RSA			101	11.97
100	Crossing the Road			118	11.70
115	Gradient Descent for SLE			111	11.81
384	Equal Hamming Distance		csfpython	23	14.48
277	The Adventure of Morse Code		zelevin	57	12.95
141	Sliding Window Search			100	11.99
291	Squirrels vs. Acorns		zelevin	52	13.11
281	Basic Tokenizer			55	13.01
186	Simple 3D Scene (cont)			84	12.29
381	Finding Squares		csfpython	23	14.48
407	River Labyrinth			15	15.19
193	Maximum Flow			80	12.37
166	Page Rank as Eigenvector			88	12.21
142	LZ77 decompression			93	12.11
432	Ball Bearing Collisions		csfpython	7	16.39
209	Suffix Array Advanced			72	12.55
421	Princess and Tiger			10	15.84
210	Ticket Puzzle			70	12.60
420	Life on a String		csfpython	10	15.84
113	Ground Zero			95	12.07
203	Tic-Tac-Toe Minimax Algorithm			70	12.60
219	Neural Network Calculation			65	12.73
112	Travelling Salesman Inverted			94	12.09
448	Button Cycles		csfpython	2	18.09
216	Cracking Linear Congruential Generator			63	12.78
351	Nicomachus			27	14.21
412	Json Fix			11	15.69
274	Two Buckets			46	13.32
132	Stream Cipher Breaking			82	12.33
439	Power Sum of Digits		csfpython	4	17.21
431	King and Rook Checkmate			6	16.62
163	Colliding Balls			72	12.55
426	Weighted Sum of Digits 2		csfpython	7	16.39
175	Algae Robot			67	12.67
107	Knight's Tour			83	12.31
335	Venus Visible			28	14.15
205	Clustering the Stars			58	12.92
390	Card Pairing Solitaire			15	15.19
230	Move-To-Front Transform			52	13.11
259	Easter Bunnies		gardengnome	45	13.35
241	Village Ways			49	13.21
200	Fizz Buzz in Asm			58	12.92
406	Wormholes of Cygnus		moxieman	11	15.69
293	Sums of Triplets			36	13.73
204	Wandering Star			55	13.01
334	Find all of the SETs		csfpython	26	14.28
218	Rain Must Fall	DE		50	13.17
212	BCD to Hex			51	13.14
315	Count the Common Factors		csfpython	29	14.09
405	Three Friendly Knights		csfpython	10	15.84
292	Factorial Trailing Zeroes			33	13.88
389	Binary Split Guessing Game		csfpython	13	15.42
409	Election Fever		csfpython	9	16.00
149	Prime Chains			61	12.83
257	Missing Records in SQL			39	13.60
403	Hi-Lo dice game			10	15.84
233	Language Study			43	13.43
376	Cartesian Tree Visualization			15	15.19
178	Maze of the Wumpus			52	13.11
443	Football League Tables		csfpython	2	18.09
147	Color Cubes Advanced			57	12.95
307	The Problem of Too Many Clues		zelevin	27	14.21
118	Maxit Single-Player			61	12.83
408	Mad Beaver in River Labyrinth			8	16.19
180	Simple Game of Sticks			48	13.24
379	Dice with Infinity Sides		telebashna	13	15.42
223	Introducing Scheme			40	13.55
330	Easter Bunnies Are Back		gardengnome	21	14.63
388	Fibonacci Guessing Game			11	15.69
393	Urban Planning		csfpython	10	15.84
338	Throwing Easter Eggs		gardengnome	19	14.80
324	Merge Sort			21	14.63
416	Socket Server		testuser	6	16.62
299	Tree Visualizer			25	14.34
354	Too Many Divisors		csfpython	16	15.08
255	LCM of a range			32	13.93
229	Burrows-Wheeler Transform			36	13.73
347	Unwanted Multiples		csfpython	17	14.98
247	Towers of Hanoi			33	13.88
183	Connect Four			43	13.43
352	Hurkle			16	15.08
297	Collatz in the Range			24	14.41
296	Tree Value	RU	csfpython	24	14.41
413	Tree Painting		csfpython	6	16.62
386	Advent Calendar Chocolate		gardengnome	10	15.84
392	Fixing an Anagram			9	16.00
270	Hexlife			27	14.21
398	Collecting Diamonds		csfpython	8	16.19
363	Language Detector			13	15.42
375	Space Invaders			11	15.69
417	Unfortunate Bubble Sort		gardengnome	5	16.89
382	Die Throw Sequences		csfpython	10	15.84
339	Parking Lot			16	15.08
353	Hurkle Hunter			14	15.30
367	Roguelike 1d			12	15.55
395	Growth of Micro-Organisms		csfpython	8	16.19
402	Game of Stones		csfpython	7	16.39
287	Palindrome Frog		csfpython	23	14.48
430	Cutting Paper		csfpython	3	17.60
284	Rotate Array In-Place			23	14.48
349	Burrows		gardengnome	14	15.30
415	Smallest Message		gardengnome	5	16.89
290	Every Leaf on Every Tree		zelevin	22	14.56
238	Bear Hunt			29	14.09
340	Zeckendorf Lite		csfpython	15	15.19
256	Rook Jump Maze			26	14.28
331	Rotating Toy Display		csfpython	16	15.08
346	Long Decimal Fractions		csfpython	14	15.30
217	Personality Swap			31	13.98
298	Revoltle		zelevin	20	14.71
243	Grille Encryption			27	14.21
312	The Shredder Conundrum		zelevin	18	14.89
234	Train Merge			28	14.15
358	Mandelbrot Set			12	15.55
249	Turing Increment			26	14.28
357	Ulam's Prime Spiral			12	15.55
286	Self-Printing Program			21	14.63
261	Easter Bunnies 2D		gardengnome	24	14.41
419	Special Digits		csfpython	4	17.21
282	Predictable Board Game		csfpython	21	14.63
169	Automated Landing			35	13.78
362	Euclid, Manhattan and Chebyshev			11	15.69
268	Logic Transformation			22	14.56
300	Run-Length Encoding			18	14.89
383	E2C2S - try harder!		gardengnome	8	16.19
271	A Knight some Trolls and a Princess		csfpython	21	14.63
313	Seven Segment Decoder			16	15.08
285	Rotate Matrix In Place			19	14.80
361	Rogue Mazes			10	15.84
387	Big Numbers		csfpython	7	16.39
441	Max versus Min		csfpython	1	18.80
404	Methane Normalization		moxieman	5	16.89
275	Three Buckets			19	14.80
394	Many Shortest Routes		csfpython	6	16.62
250	Turing Clone			21	14.63
344	Throwing Easter Eggs Part 2		gardengnome	11	15.69
213	Micro-Life	SK		24	14.41
319	Tower of Hanoi Rules		csfpython	13	15.42
326	Sum Them Forth			12	15.55
314	The Sorites Solution		zelevin	13	15.42
220	Neural Network Training			22	14.56
260	Low Cost Road Network		csfpython	18	14.89
332	Easter Bunnies 2D Are Back		gardengnome	11	15.69
341	Zeckendorf Advanced		csfpython	10	15.84
336	Currency Arbitrage			10	15.84
380	Treap Study			6	16.62
289	The Case of the Desperate Mastermind		zelevin	14	15.30
231	Dice Black Jack			19	14.80
378	Space Invaders Automation			6	16.62
262	Easter Bunnies 2D Advanced		gardengnome	16	15.08
424	New Towers of Hanoi		csfpython	2	18.09
295	Vigenere Cipher Cracker			13	15.42
365	Flower Border Arrangements		csfpython	7	16.39
306	Line Drawing Algorithm			12	15.55
222	Easter Eggs Advanced			19	14.80
221	XWords		quandray	19	14.80
316	Apogee			11	15.69
303	Towers Under Cover			12	15.55
254	Rule 30 by Turing			16	15.08
276	Lucky Pairs		csfpython	14	15.30
288	Langton's Ant		csfpython	13	15.42
410	Village Door Shuffle		csfpython	3	17.60
263	Easter Bunnies 3D		gardengnome	15	15.19
422	Mabinogion Sheep		moxieman	2	18.09
266	Pancake Sorting			14	15.30
343	Village of Ticks			8	16.19
311	The Mirror Maze		zelevin	10	15.84
391	Scout Proficiency Badges		csfpython	4	17.21
350	Colourful Egg Sequences		gardengnome	7	16.39
309	Board Game Sequences		csfpython	10	15.84
279	Two Buckets Advanced		csfpython	12	15.55
320	Accordion		pearlbarley	9	16.00
333	Happy Triplets			8	16.19
235	Train Merge Advanced			15	15.19
345	Elliptic Curves Basics			7	16.39
242	Comment Stripper			14	15.30
327	Dobbin's Long Journey		csfpython	8	16.19
325	Ultimate Sort Trial			8	16.19
305	The Catacombs of Chronos		zelevin	9	16.00
397	Trading Bot			3	17.60
396	Chocolate Triangles and BF		moxieman	3	17.60
237	Road Network Destruction			13	15.42
267	Turing Maze			11	15.69
328	Beep Beep Beep			7	16.39
310	Board Game Sequences Advanced		csfpython	8	16.19
227	Hashtable Implementation			13	15.42
342	Adaptive Arithmetic Coding			6	16.62
308	Circle Drawing Algorithm			8	16.19
322	Gray Decoder			7	16.39
304	Ordered Brackets		csfpython	8	16.19
252	Shadok and Gibis			11	15.69
215	Klotski	SK		13	15.42
264	Party Presents		csfpython	10	15.84
370	Jewels			4	17.21
225	Hamurabi			12	15.55
369	Flappy Bird			4	17.21
226	Multiplicative Persistence Backtrace			11	15.69
283	Predictable Board Game on 10 Boards		csfpython	8	16.19
224	Transposing List of Lists			11	15.69
321	Hanoi Tower Heights		csfpython	6	16.62
355	Robots Game			4	17.21
251	Radio Spies			9	16.00
248	Christmas Puzzle			9	16.00
373	Railroad Rat		csfpython	3	17.60
239	Foxes and Geese			9	16.00
348	Trick-Taking Game			4	17.21
280	Three Buckets Re-visited		csfpython	7	16.39
302	Sound-Controlled Robot			6	16.62
278	Polyomino Generation			7	16.39
232	Shift Register Randomizer			9	16.00
272	Hexplore			7	16.39
236	Is the Earth Flat			8	16.19
356	Robots Game Autoplay			3	17.60
273	Logic Glitches			6	16.62
240	Playfair Cipher Cracking			7	16.39
317	Launch to Orbit			4	17.21
228	Maze Mapping Robot			6	16.62
318	Launch to Orbit automated			2	18.09