Code challenge from lantmateriet.se
Yesterday I found a code challenge on http://www.lantmateriet.se/knackkoden that I decide to take a look on. We first need to decode the base 64 encoded text to get the actual instructions.
Problem
Gör ett program som skriver ut talen i mängden {1, 2, …, 10500} i stigande ordning.
Om talet är jämnt delbart med 3 så ska www. skrivas ut istället för själva talet.
Om talet är jämnt delbart med 5 så ska lantmateriet skrivas ut istället för själva talet.
Om talet är jämnt delbart med 7 så ska .se skrivas ut istället för själva talet.
Om talet är jämnt delbart med 3, 5 och 7 så ska www.lantmateriet.se skrivas ut istället för själva talet.
Inga nyradstecken ska skrivas ut, utan allt ska skrivas ut på en och samma rad.
Utskriften inleds enligt nedan:
1 2 www. (och så vidare…)
Inget mellanrum som sista tecken.
MD5-summan av utskriften är 402087a86f4fbd5d01d80baec13fddc5
Men vad är SHA-1-summan?
Solution
Anyone that can come up with another or better solution?
public static void Main() { const int NumberOfIterations = 10500; var sb = new StringBuilder(); for (var i = 1; i <= NumberOfIterations; i++) { if (i % 3 != 0 && i % 5 != 0 && i % 7 != 0) { sb.Append(i + " "); continue; } if (i % 3 == 0 && i % 5 == 0 && i % 7 == 0) { sb.Append("www.lantmateriet.se "); continue; } if (i % 3 == 0) { sb.Append("www. "); } else if (i % 5 == 0) { sb.Append("lantmateriet "); } else if (i % 7 == 0) { sb.Append(".se "); } } var resultString = sb.ToString().TrimEnd(); if ("402087a86f4fbd5d01d80baec13fddc5" != GetMD5HashData(resultString, Encoding.UTF8)) { Console.WriteLine("Error missmatch MD5 hash"); return; } Console.WriteLine("The SHA1 hash is:" + GetSHA1HashData(resultString, Encoding.UTF8)); } |
You can download the complete solution here: LantmaterietKnackkoden
System.UnauthorizedAccessException: Access to the path is denied when using System.OI.FileStream
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using (FileStream fs = new FileStream(filePath, FileMode.Open)) { … } |
Make sure, you ask for what you really need. If your application needs only Read access to a file, make sure to specify that in your FileStream constructor.
using (FileStream fs = new FileStream(filePath, FileMode.Open, FileAccess.Read)) { … } |
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private static void SetAppSettings(string key, string value) { Configuration config = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None); config.AppSettings.Settings[key].Value = value; config.Save(ConfigurationSaveMode.Modified); ConfigurationManager.RefreshSection("appSettings"); } |
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Example project
In this example you will be able to connect to a TFS server and get all work items based on project and iteration path listed.
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JustDecompile
http://www.telerik.com/products/decompiling.aspx
Feature
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• Create visual studio projects
• Extract resources from assemblies
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• Command line support
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http://divebuddyplanner.codeplex.com
Is decompression planning application for windows phone 7. The algorithm used is based on Buhlmann ZHL16A, ZHL16B and ZH 17B with m-value gradient conservatism. Both air, nitrox and trimix diving is supported.
Scrumy
https://scrumy.codeplex.com
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Earlier i wrote a blog post about isolating DateTime.Now with disposable pattern. Here is a little more advance example for the static method Directory.Exists.
So here is the simple example of product code that we want to test
public void ProcessFiles(string path) { if (!DirectoryIsolator.Exists(path)) { throw new ArgumentException("Path doesn't exist"); } } |
This first test method is simple setting the return value to false before calling the product code
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How would you test correctness of bellow simple example?
public bool IsIt2012 { get { return (DatemTime.Now.Year == 2012); } } |
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using System; using System.ServiceModel; using System.Runtime.Serialization; namespace Test.DataContracts { [DataContract(Namespace = "Testing", Name = "JobResult")] public enum JobResult { [EnumMember] Passed = 0, [EnumMember] Failed = 1, [EnumMember] Running = 2, [EnumMember] TestFailure = 3, [EnumMember] Queued = 4, [EnumMember] JobNotFound = 5 } } |