Let's walkthrough the solution to the second code challenge.
For this challenge, we need to use the forEach method to copy 0:00 only the first 2 characters of each string in the days array. 0:03 And store the abbreviations in the dayAbbreviations array. 0:07 Like I did earlier, I'm going to copy and paste the code for 0:11 this challenge into the Atom text editor in order to make the code easier to read. 0:14 So the days array contains seven strings, one string for each day of the week. 0:22 And what we want to end up with is an abbreviation for each of those strings or 0:28 each of those days. 0:32 So Su for Sunday. 0:34 Mo for Monday and so on. 0:37 Let's look at my solution. 0:39 Again, I started by adding the call for each method. 0:41 And then, the anonymous call back function using arrow function syntax. 0:45 So, days.forEach. 0:49 And, I use day for the current value parameter name. 0:54 Day, and then a fat arrow. 0:57 Then I added a set of curly braces to define a code block. 1:00 Let's add a variable for the dayAbbreviation. 1:04 So const dayAbbreviation. 1:06 To get the first two characters of each day string, I used the slice method. 1:12 So day.slice. 1:16 Now, you could also use substring. 1:19 Or substr. 1:22 Both of those methods would also work fine. 1:24 I'm going to go ahead and switch back to the slice method. 1:27 The first parameter for the slice method is the begin index. 1:31 The zero based index at the string extraction should begin with. 1:34 The second parameter is the end index. 1:39 The index that the string extraction should end with. 1:42 It's worth noting that the character at this index won't be included. 1:45 Let's take a look at the string for Sunday. 1:49 So S is at an index of 0. 1:52 U is at an index of 1. 1:55 And n is at an index of 2. 1:58 So we want to extract Su, but not n. 1:59 So with the slice method, we'll supply the 2. 2:05 Meaning that we want to select up to but not including the index of 2. 2:08 Now that I have my dayAbbreviation, I just pushed it onto the dayAbbreviations array. 2:14 So dayAbbreviations.push(dayAbbreviation). 2:20 And that's my solution. 2:26 Now, we can leave it just as it is, or we could simplify it. 2:28 We can do that by eliminating the intermediate variable, (dayAbbreviation). 2:33 To do that, let's cut this code and place it inside of the call to the push method. 2:38 Then we can eliminate this line of code. 2:44 And we can actually eliminate the code block itself. 2:47 There. 2:51 That looks a little cleaner, doesn't it? 2:53 Ready for the next challenge? 2:55 We'll see you in a bit with my solution. 2:56
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