Gabriel Vanca gabriel-vanca

Inspired by this article. Neat tricks for speeding up integer computations.

Note: cin.sync_with_stdio(false); disables synchronous IO and gives you a performance boost. If used, you should only use cin for reading input (don't use both cin and scanf when sync is disabled, for example) or you will get unexpected results.

Multiply by a power of 2

x = x << 1; // x = x * 2

using System.Collections.Generic;
using System.Linq;

namespace Utility.Extensions
{
    public static class IEnumerableExtensions
    {
        public static IEnumerable<(T item, int index)> WithIndex<T>(this IEnumerable<T> self)
 =&gt; self?.Select((item, index) =&gt; (item, index)) ?? new List&lt;(T, int)&gt;();

	<#
	.SYNOPSIS
	Retries a Powershell command n-times upon failure.

	.DESCRIPTION
	The cmdlet is capable of retrying a PowerShell command passed as a [ScriptBlock] according to the user defined number of retries and time between retries.

	.PARAMETER ScriptBlock
	PoweShell command(s) as a ScriptBlock that will be executed and retried in case of Errors.
	Make sure the script block throws an error when it fails, otherwise the cmdlet won't run the retry logic.

	# MS Security bulletin: https://learn.microsoft.com/en-us/security-updates/SecurityAdvisories/2015/3009008

	# NOTE: This registry change requires that the system be restarted.

	Function Test-RegKeyExists {
	param (
	$key
	)

	If (!(Test-Path -Path $key)) {

	<#
	.SYNOPSIS
	A brief description of the function or script. This keyword can be used only once in each topic.

	.DESCRIPTION
	A detailed description of the function or script. This keyword can be used only once in each topic.

	.COMPONENT
	The name of the technology or feature that the function or script uses, or to which it is related.