Problem Solutions


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Here we discuss the solutions of problems.

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Topic Posts Created Last post
[45 Card Shuffler] Doesnt Random mean different results? 2 Jul 15 2017 Jul 15 2017 04:20
[Task#180] Is Simple Game of Sticks really simple? 6 Dec 6 2014 Jul 12 2017 22:18
Smoothing the weather - Java precision 3 May 25 2017 Jun 3 2017 09:18
Problem 66 Caesar Cipher Cracker 1 May 2 2017 May 2 2017 10:33
[Problem 187] Static Web Page - No HTTPS 1 Apr 30 2017 Apr 30 2017 22:45
Arithmetic Progression some problems 3 Mar 25 2017 Apr 3 2017 20:25
[Task#112] Travelling Salesman Inverted 2 Feb 19 2017 Apr 3 2017 20:15
[Problem 36] Code Guessser 11 Jan 20 2017 Mar 29 2017 08:58
Fibonacci positions (task 67) in JavaScript 11 Aug 2 2015 Mar 24 2017 01:25
[Task83] Graph Generator 3 Mar 10 2017 Mar 14 2017 08:56
[Task#113] How to solve Ground Zero 4 Aug 3 2014 Feb 27 2017 17:16
22 Two Printers 4 Feb 5 2017 Feb 6 2017 19:50
[Task#6] Problems with Rounding 4 Jan 28 2017 Jan 30 2017 14:13
[Task#51] [Problem 51] Dungeons and Dragon Dice 1 Jan 30 2017 Jan 30 2017 12:09
Page Rank as Eigenvector 4 Jan 15 2016 Jan 30 2017 07:03
[Problem 131] Four Pics One Word 3 Jan 27 2017 Jan 28 2017 04:31
[Task#43] Dice Rolling 2 Jan 16 2017 Jan 24 2017 21:04
Luhn Algorithm need help 3 Jan 21 2017 Jan 21 2017 13:59
Share Price Volatility please help 2 Jan 16 2017 Jan 16 2017 20:46
Parity Control 3 Jan 8 2017 Jan 8 2017 10:39
[Task#213] Micro-Life ranking system 8 Nov 11 2015 Jan 3 2017 21:12
[Task#20] Clumsy solution 2 Jan 3 2017 Jan 3 2017 19:13
Modular Calculator 7 Jun 30 2015 Dec 22 2016 19:31
Problem 54 - Pythagorean Triples 3 Dec 17 2016 Dec 18 2016 20:40
Problem 117 Divide by Two 6 Jun 29 2016 Dec 15 2016 17:37
[Task#212] How to calc the solution size 10 Oct 8 2015 Dec 15 2016 07:58
46 Tic-Tac-Toe Problem statement 3 Dec 12 2016 Dec 12 2016 09:03
A little problem with array checksums using PHP 3 Dec 9 2016 Dec 10 2016 08:51
basic html 2 Nov 29 2016 Nov 29 2016 13:56
[Task#21] Array Counters 3 Nov 25 2016 Nov 25 2016 17:23
Median of three 3 Nov 21 2016 Nov 21 2016 16:18
Array CheckSum What is wrong? 8 Nov 8 2016 Nov 12 2016 00:20
Task 59 Bulls and Cows 3 Nov 3 2016 Nov 3 2016 11:26
[Task 23] Error when calculating array checksum 3 Aug 19 2016 Oct 12 2016 19:34
[Task#108] Star Medals what is the core idea of this task? (Star Medals 108) 3 Oct 5 2016 Oct 7 2016 11:03
46 Tic-Tac-Toe one in 17 answers is wrong What am I missing? 2 Oct 4 2016 Oct 5 2016 17:26
help with interactive http tasks 3 Oct 4 2016 Oct 4 2016 13:14
Issues connecting to interactive problem server? 3 Jul 13 2016 Sep 29 2016 11:00
Share price volatility - Standard deviation issue task 39 2 Sep 27 2016 Sep 27 2016 18:42
Most Frequent Word (Task 70) 10 Sep 19 2015 Sep 22 2016 19:56
Problem 61 - Prime Numbers Generation 7 Nov 9 2014 Sep 11 2016 19:25
Safe landing 4 Sep 3 2016 Sep 4 2016 09:39
Rotate string the answer tallies But shows it is wrong 4 Aug 30 2016 Sep 3 2016 15:21
Billiard Ball bounce from bottom and right borders problem 10 Aug 26 2016 Aug 27 2016 15:58
Clarifying the task --- Breadth First Search --- Task 154 14 Aug 24 2016 Aug 26 2016 13:22
Need help(task 22) 5 Aug 26 2016 Aug 26 2016 12:07
Problem 35 Savings Calculators 3 Aug 10 2016 Aug 10 2016 12:24
Bubble Sort 3 Aug 7 2016 Aug 7 2016 13:51
Problem 78 (Bezier Curves) 2 Aug 1 2016 Aug 1 2016 00:56
Depth First Search 10 Jul 24 2015 Jul 14 2016 09:22
Is there a mistake in example for problem 156 (Task Luhn Algorithm) 3 Jul 6 2016 Jul 7 2016 11:47
fibbonacci squared but this always field 2 Jun 17 2016 Jun 20 2016 15:25
Say-100 request 1 Jun 17 2016 Jun 17 2016 14:04
[task 18] on C Sharp 4 Jun 2 2016 Jun 7 2016 14:20
Example for the Cows and Pigs problem is incorrect 2 Jun 2 2016 Jun 3 2016 20:30
[Task#208] Known string neighborhood searching algorithms 1 May 26 2016 May 26 2016 18:55
Problem 141 description 16 Aug 7 2014 May 22 2016 17:20
Task 16 Average of an Array - Cplusplus 5 May 2 2016 May 4 2016 14:34
problem with task 24 2 Apr 25 2016 Apr 25 2016 19:00
Problem 27 Bubble Sort help 4 Nov 13 2015 Apr 25 2016 11:50
Problem 66 my code doesnt decipher all sentences dont know whats wrong 2 Apr 16 2016 Apr 24 2016 14:32
Problem 176 - getting the right answer but always losing the game - Python3 2 Apr 7 2016 Apr 7 2016 17:55
Color Cubes Advanced 2 Apr 2 2016 Apr 4 2016 08:21
Problem 8 [Java] 1 Apr 3 2016 Apr 3 2016 12:31
Aglae Robot 3 Apr 1 2016 Apr 1 2016 12:55
[Task#21] Array Counter - Quick Question 3 Mar 22 2016 Mar 23 2016 16:03
[Task#165] [problem 165] Safe Landing - Dont know whats wrong with my code 4 Mar 22 2016 Mar 22 2016 11:10
[Task#150] Introducing Regexps 2 Mar 13 2016 Mar 20 2016 05:41
[Task#118] Single-Player Maxit 1 Mar 20 2016 Mar 20 2016 02:06
[Task#61] Prime numbers generator c sharp 7 Aug 6 2015 Mar 14 2016 21:47
LZ77_decompression 1 Mar 11 2016 Mar 11 2016 16:40
Problem 57 Smoothing the Weather 3 Mar 10 2016 Mar 11 2016 15:55
Problem 33 4 Feb 20 2016 Mar 9 2016 22:29
Problem 67 6 Aug 27 2014 Mar 3 2016 19:36
Bubble in Array java 3 Feb 29 2016 Mar 1 2016 02:43
Calculation of Pi 6 Sep 27 2015 Feb 26 2016 19:42
Help with Shannon-Fano Coding 2 Feb 23 2016 Feb 24 2016 10:49
156 Luhn Algorithm 3 Feb 19 2016 Feb 21 2016 12:07
Problem 36 2 Feb 20 2016 Feb 21 2016 06:38
Problem 35 3 Feb 20 2016 Feb 20 2016 16:56
Selection Sort (120) 3 Feb 17 2016 Feb 17 2016 15:40
task 23 Bubble in Array 3 Feb 15 2016 Feb 16 2016 16:56
Problem 22 2 Feb 14 2016 Feb 14 2016 19:33
Some numbers do not match on 81 (Bit Count) 3 Feb 4 2016 Feb 4 2016 22:12
Look and Say Binary 179 4 Jan 31 2016 Feb 2 2016 12:59
NimGame 177 2 Jan 29 2016 Jan 30 2016 07:55
[Task#69] Fibonacci Divisibility 3 Jan 28 2016 Jan 29 2016 06:10
Query String Parameters --- the checker wont accept my URL Why? 6 Jan 20 2016 Jan 21 2016 19:25
Weighted sum of digits 6 Jan 16 2016 Jan 18 2016 20:57
Help with Bezier Curve (78) 1 Jan 18 2016 Jan 18 2016 17:05
Uphill Shooting (99) 7 Jan 8 2016 Jan 10 2016 08:09
Dynamic Web Page 2 Jan 7 2016 Jan 7 2016 14:11
Help with 32 Josephus Problem 6 Aug 11 2014 Jan 7 2016 11:40
Problem 163 Colliding Balls 9 Feb 8 2015 Jan 5 2016 15:39
Frodo and Black Riders 5 Jan 2 2016 Jan 3 2016 02:39
24 neumanns 3 Jan 1 2016 Jan 2 2016 16:01
[Task#19] 19 - Matching Brackets 1 Dec 31 2015 Dec 31 2015 19:17
Possible error or unexplained feature? 2 Dec 28 2015 Dec 28 2015 23:16
Problem 20 vowel count 9 Dec 22 2015 Dec 28 2015 09:21
17 Array Checksum 3 Dec 25 2015 Dec 26 2015 15:25
Binary Search in Array - IP database problem 3 Nov 4 2014 Dec 22 2015 15:03
Easter Eggs 5 Dec 8 2015 Dec 11 2015 14:41
task 33 Parity Control --- one space symbol before the answer 1 Dec 9 2015 Dec 9 2015 14:43
Average of an array rounding problem 7 Jun 27 2015 Dec 8 2015 08:55
Travelling Salesman 1 Dec 6 2015 Dec 6 2015 21:35
Help with Rounding (task 6) 5 Oct 24 2014 Dec 5 2015 08:01
Task 13 - Weighted sum of digits 4 Dec 1 2015 Dec 2 2015 19:24
Combinations counting (task 128) - Whats wrong with my code? 6 Oct 13 2014 Nov 30 2015 08:40
Problem 15 Max Array - Results match expected but still wrong 2 Nov 29 2015 Nov 29 2015 21:32
[Task#192] Gangster Battles 3 Nov 19 2015 Nov 20 2015 19:57
Problem 144 Modular Inverse - sometimes solutions exist 2 Nov 18 2015 Nov 19 2015 05:39
Random Search Optimization - transition problems? 1 Nov 18 2015 Nov 18 2015 16:56
17 problem? 4 Nov 16 2015 Nov 16 2015 20:29
Girls and pigs - just a note 2 Nov 12 2015 Nov 12 2015 15:51
[Task#33] I thought I would get a cool secret message D 4 Mar 19 2015 Nov 6 2015 21:18
[Task#204] Wandering Star Algorithm 5 Mar 11 2015 Nov 6 2015 11:21
Java error on this site 2 Nov 6 2015 Nov 6 2015 11:20
[Task#169] Automated Landing answer precision 4 Oct 28 2014 Nov 6 2015 05:40
Problem 21 ? 5 Nov 4 2015 Nov 4 2015 13:19
[Task#166] Page Rank as an Eigenvector 4 Oct 19 2015 Nov 3 2015 09:18
Task173 - Chords of music 4 Oct 19 2015 Oct 20 2015 07:04
[Task#23] Problem with Task 23 Two printers 6 Oct 16 2015 Oct 16 2015 14:44
Cards Shuffling Problem 45 5 Oct 11 2015 Oct 14 2015 14:44
Employees Web App (task 199) 3 Oct 9 2015 Oct 9 2015 06:39
Problem 34 Binary Search 17 Jan 20 2015 Oct 7 2015 16:01
Frodo and Black Riders 15 Oct 2 2015 Oct 3 2015 12:16
Suffix Array Advanced 4 Oct 2 2015 Oct 3 2015 09:48
[Task#169] Check this out 3 Oct 1 2015 Oct 2 2015 09:50
Problem 09 Java 3 Sep 30 2015 Oct 1 2015 15:06
Crossing the Road 5 Sep 28 2015 Sep 29 2015 06:26
Card Shuffling (task 45) 4 Sep 21 2015 Sep 22 2015 09:02
[Task#40] Paths in the Grid - Feedback? (Task 40) 6 Sep 12 2015 Sep 19 2015 21:16
Problem 14 C 15 Aug 12 2015 Sep 19 2015 11:11
Clarification for 210 Ticket Puzzle 7 Aug 30 2015 Aug 30 2015 15:59
Problem 33 Parity Control 5 Aug 15 2015 Aug 16 2015 06:23
Bicycle Race Examples 1 Aug 14 2015 Aug 14 2015 20:03
Difficulty solving problem 23 bubble in array 3 Aug 13 2015 Aug 13 2015 23:21
[Problem 67] Problem in C with size of input 8 Dec 14 2014 Aug 12 2015 06:45
Task 67 - Test-cases exceed range of long type (java) 5 Aug 11 2015 Aug 11 2015 17:05
Problem 176 interactive problem Sending correct answer but always end up losing game 6 Aug 8 2015 Aug 8 2015 09:45
Bubble in Array-- my algorithm solves the example lists but not the test case 4 Aug 4 2015 Aug 4 2015 19:20
Neumanns Random Generator 3 Aug 2 2015 Aug 2 2015 17:09
[Task#134] Bad Practice? 6 Jul 27 2015 Jul 28 2015 16:17
[Task#12] Modulo and time difference - request for code review (Python) 5 Jul 27 2015 Jul 28 2015 10:06
Easter Eggs 5 Jul 24 2015 Jul 24 2015 12:18
Gradient Calculation (task 101) 2 Jul 23 2015 Jul 23 2015 10:42
17 Array Checksum - Is my checksum algorithm correct? 3 Jul 21 2015 Jul 21 2015 21:05
[Task#80] Problem 80 Solution Explaination 5 Jul 19 2015 Jul 19 2015 21:13
[Task#205] Problem with Clustering the Stars checker 2 Jul 19 2015 Jul 19 2015 14:20
[14] [C] How do we deal with large intermediate numbers? 6 Jul 18 2015 Jul 18 2015 21:53
Clustering the Stars 1 Jul 18 2015 Jul 18 2015 17:24
[Important] Problem 104 Solution Explanation - Spoiler alert 3 Jul 17 2015 Jul 17 2015 16:08
Array Counter (task 21) 4 Jul 13 2015 Jul 15 2015 20:32
Gradient Calculation 13 Jul 9 2015 Jul 11 2015 10:17
[Task#50] Palindrome problem 6 Jul 7 2015 Jul 10 2015 10:15
Triangle Area rounding problem 3 Jul 1 2015 Jul 8 2015 11:00
Im doing something wrong? 14 Jun 26 2015 Jul 2 2015 15:36
Task14 Problem 3 Jun 29 2015 Jun 29 2015 10:39
Unable to do the maths behind problem 10 2 Jun 27 2015 Jun 27 2015 19:01
DungeonsAndDragonsDice 6 Jun 24 2015 Jun 25 2015 21:55
Flying Text Screensaver 2 Jun 21 2015 Jun 22 2015 11:53
Error in 114 Gradient Descent for SLE 2 Mar 13 2015 Jun 15 2015 22:44
Task 144 Explanation 3 May 31 2015 Jun 8 2015 21:50
Problem 119 Brain Fibo 2 Jun 4 2015 Jun 8 2015 20:40
Girls and pigs number of solutions 4 May 19 2015 May 25 2015 06:41
Is the testing system works as it should? 3 May 21 2015 May 21 2015 23:30
Problem 22 2 May 15 2015 May 17 2015 06:32
A question about Problem 119 Brain Fibo 3 May 1 2015 May 1 2015 22:41
[Task 80] explanation on authors notes on the problem ? 4 Apr 20 2015 Apr 29 2015 06:32
[Task#103] Easter Eggs 4 Jan 20 2015 Apr 29 2015 06:30
[Task#104] Triangle Area revision on authors notes 1 Apr 15 2015 Apr 15 2015 20:49
Task 14 - C - Getting wrong solution and unable to locate why 3 Apr 12 2015 Apr 12 2015 20:57
[Task 35] Savings Calculator wrong result ? 6 Apr 9 2015 Apr 10 2015 05:31
Task 14 - Im getting the wrong result and I dont know why Help 3 Apr 6 2015 Apr 7 2015 10:20
[187] Static Web Page 2 Apr 3 2015 Apr 6 2015 08:54
Problem 40 Paths in the Grid - No Output? 4 Mar 31 2015 Apr 5 2015 02:39
[190] Query String Parameters 1 Apr 4 2015 Apr 4 2015 01:22
Problem 127 - Anagram 4 Apr 3 2015 Apr 3 2015 21:40
Two Printers 9 Dec 26 2014 Mar 25 2015 00:11
Task 13 - Weighted sum of digits 12 Feb 17 2015 Mar 4 2015 10:35
What wrong with dancing pairs? 7 Feb 22 2015 Feb 23 2015 14:36
Enumerating Combinations (task 129) 6 Feb 16 2015 Feb 21 2015 07:47
[Task#201] What I have done 7 Feb 19 2015 Feb 20 2015 19:45
[Task#86] Simple brainfk interpreter (private) 3 Feb 13 2015 Feb 13 2015 18:09
Fibonacci Divisibility (69) - long numbers 5 Feb 1 2015 Feb 3 2015 08:39
My problem with Dynamic Web Page at PythonAnywhere 5 Feb 1 2015 Feb 2 2015 21:04
Problem with PythonPrintHexStr task 3 Feb 1 2015 Feb 1 2015 08:45
Hexagonal Grid 7 Jan 29 2015 Jan 29 2015 20:49
[Task#199] Employees Web App 3 Jan 28 2015 Jan 28 2015 14:54
[Task#193] Maximum Flow 3 Jan 18 2015 Jan 19 2015 14:56
Tricky Printing - Brainfuck problem 3 Jan 17 2015 Jan 17 2015 17:47
task 16 Average of an array I dont get why this rounding doesnt work 2 Jan 17 2015 Jan 17 2015 17:18
Flow Network 6 Jan 17 2015 Jan 17 2015 17:07
[Task#36] code guesser Did anyone solve it a better way 4 Jan 4 2015 Jan 15 2015 10:32
Problems with problem 116 5 Aug 18 2014 Jan 12 2015 15:45
[Task#14] What is the use of this problem? 2 Jan 12 2015 Jan 12 2015 13:09
Static Web Page - https 3 Jan 8 2015 Jan 8 2015 20:05
Prime Chains 12 Aug 20 2014 Dec 24 2014 13:22
[Problem 50] CPU time limit exceeded (core dumped) 3 Dec 21 2014 Dec 22 2014 14:36
Counting Vowels Problem 3 Dec 4 2014 Dec 4 2014 07:56
[Task#128] Combinations Counting 4 Nov 30 2014 Dec 1 2014 15:42
DFS works fine with example but still fails (Task 155) 4 Nov 26 2014 Dec 1 2014 13:28
[Task#31] Rotate String 4 Nov 25 2014 Nov 29 2014 11:40
[Task#179] Look and Say binary 3 Nov 28 2014 Nov 28 2014 13:27
[Task#178] Maze of the Wumpus - methods to generate maze 2 Nov 24 2014 Nov 24 2014 10:15
C Sharp Problem 67 2 Nov 19 2014 Nov 20 2014 06:04
[Task#175] Algae Robot - tips and trics 4 Nov 19 2014 Nov 19 2014 15:08
Sequence of Squares (task 126) 3 Nov 15 2014 Nov 16 2014 07:36
[Task#174] The last digits 3 Nov 13 2014 Nov 13 2014 21:05
[Task#173] Chords of Music - test data correctness 7 Nov 10 2014 Nov 11 2014 14:06
Bit Count confusion (task 81) 11 Nov 6 2014 Nov 9 2014 16:05
159 Hard Life confirmation 8 Oct 5 2014 Nov 7 2014 16:15
[Task#167] BF - Copy Line 3 Oct 24 2014 Oct 26 2014 05:49
[Task#168] Caesar meets BF 11 Oct 21 2014 Oct 22 2014 05:37
[Task#167] Copy Line checker 8 Oct 20 2014 Oct 21 2014 08:18
[Task#159] Hard Life Solutions 3 Oct 6 2014 Oct 7 2014 04:39
Hamming Codes 3 Sep 16 2014 Sep 16 2014 13:37
Palindromic Primes 19 Sep 5 2014 Sep 8 2014 11:27
[Task#155] Solution visualization 6 Sep 3 2014 Sep 4 2014 10:44
problem 57 6 Aug 25 2014 Aug 26 2014 18:05
[Task#151] Word Ladders solving methods 13 Aug 23 2014 Aug 25 2014 12:09
Introducing Regexps - minor problems 5 Aug 22 2014 Aug 22 2014 17:56
[Task#147] Color Cubes Advanced 6 Aug 19 2014 Aug 19 2014 21:41
[Task#145] Two solutions for task 145 12 Aug 12 2014 Aug 13 2014 01:55
[Task#145] Task 145 is that OK Oh and its really looks nothing like Python 2 Aug 12 2014 Aug 12 2014 09:39
[Task#144] Another algorithm for Task 144 private 1 Aug 12 2014 Aug 12 2014 08:04
Modular Inverse unittest 11 Aug 11 2014 Aug 11 2014 15:55
Minor corrections for 143 and 144 2 Aug 11 2014 Aug 11 2014 11:06
Correction in Task 124 2 Aug 9 2014 Aug 9 2014 05:07