Loops vs HashSets

-

When looking up data in memory from a large collection, a HashSet or Dictionary is much, much faster than looping through an ordinary collection.

This example uses strings - if you run the same code but treat them as GUIDs, the numbers improve quite a bit, but the difference between array and HashSet is still tremendous.

View code on GitHub

Comments

Post a Comment

Popular posts from this blog

Left Join in Entity Framework

-
Image
If you need a left join in Entity Framework, you have a couple options. First, if you’re using a real foreign key that just happens to be nullable, then you can use the regular navigation properties. But if you’re doing a left join manually, or with other factors, then you need to do things just a little differently: Suppose we have the following database: create table dbo . Foods ( FoodID int not null identity primary key , FoodName varchar ( 100 ) not null ) ; go insert dbo . Foods ( FoodName ) values ( 'Pizza' ) , ( 'Chicken' ) , ( 'Potatoes' ) , ( 'Broccoli' ) ; go create table dbo . People ( PersonID int not null identity primary key , FirstName varchar ( 100 ) not null , FavoriteFoodID int null , constraint FK_Person_FavoriteFoodID foreign key ( FavoriteFoodID ) references dbo . Foods ( FoodID ) ) ; go insert dbo . People ( FirstName , FavoriteFoodID ) values ( 'John' , 1 ) , ...
Read more

JavaScript Spread Operator

-
Image
With JavaScript's spread operator, you can clone an array, or inject the values into another array, or into the parameters of a function. You also can combine the properties of two objects when you build it using an object literal. View code on GitHub
Read more

Create Bootable USB from Windows

-
I've had amazingly bad luck with different programs and operating systems, just trying to create bootable thumb drives. In Windows, when creating a Windows bootable USB, this seems to work, with the instructions found here : No promises that this will work everywhere. C:\> diskpart Diskpart> list disk Diskpart> sel disk 1  <-- (the number of your usb) Diskpart> clean Diskpart> create part pri Diskpart> format fs=ntfs quick Diskpart> Active Diskpart> Assign Now copy the install files to the drive, and use it to boot.
Read more