Intermediate Exercism • csharp

Gigasecond

Challenge Overview

Given a moment, determine the moment that would be after a gigasecond has passed.

Visit the gigasecond exercise on Exercism to read the full instructions and download the exercise files.

Dig Deeper

Use AddSeconds

AddSeconds

using System;

public static class Gigasecond
{
    public static DateTime Add(DateTime birthDate)
    {
        return birthDate.AddSeconds(1_000_000_000);
    }
}

The DateTime class has an AddSeconds() method that takes the number of seconds to add to the DateTime instance. We then simply pass in the gigasecond value and a new DateTime instance is returned with the amount of seconds specified added to it.

Shortening

There are two things we can do to further shorten this method:

Remove the curly braces by converting to an expression-bodied method
Replace 1_000_000_000 with 1e9, which is the same number but in scientific notation

Using this, we end up with:

public static DateTime Add(DateTime birthDate) => birthDate.AddSeconds(1e9);

Use a TimeSpan

TimeSpan

using System;

public static class Gigasecond
{
    public static DateTime Add(DateTime birthDate)
    {
        return birthDate + TimeSpan.FromSeconds(1_000_000_000);
    }
}

The DateTime class supports adding a TimeSpan instance via the + operator. We then simply use the + operator on the DateTime instance and pass it the gigasecond in the form of a TimeSpan by using its TimeSpan.FromSeconds() factory method. This will return a new DateTime instance with the amount of seconds represented by the TimeSpan added to it.

Shortening

There are two things we can do to further shorten this method:

Remove the curly braces by converting to an expression-bodied method
Replace 1_000_000_000 with 1e9, which is the same number but in scientific notation

Using this, we end up with:

public static DateTime Add(DateTime birthDate) => birthDate + TimeSpan.FromSeconds(1e9);

Source: Exercism csharp/gigasecond