.Net Tips — Use LINQ to create pairs of adjacent elements from a collection

Suppose you have an array of numbers, say, [1, 3, 5, 7, 9, …], and you want to pair each element up with its neighbour in the array, e.g. [[1, 3], [3, 5], [5, 7], [7, 9], …].

Project Euler — Problem 81 Solution

Problem

In the 5 by 5 matrix below, the minimal path sum from the top left to the bottom right, by only moving to the right and down, is indicated in bold red and is equal to 2427.

Find the minimal path sum, in…

S3 — Use using block to get the stream

When you’re using the Amazon S3 client, have you come across the occasional exception that says something like one of these exception messages:

“The request was aborted: The connection was closed unexpectedly”

.Net Tips — use [field:NonSerialized] to stop serializing your event handlers

In C#, when you define an event in your class, e.g.:

Project Euler — Problem 79 Solution

Problem

A common security method used for online banking is to ask the user for three random characters from a passcode. For example, if the passcode was 531278, they may ask for the 2nd, 3rd, and 5th characters; the expected reply…

Project Euler — Problem 145 Solution

Problem

Some positive integers n have the property that the sum [ n + reverse(n) ] consists entirely of odd (decimal) digits. For instance, 36 + 63 = 99 and 409 + 904 = 1313. We will call such numbersreversible; so 36, 63, 409, and 904…