FAQ: Learn Java: ArrayLists - Getting an Item's Index

Frequently Asked Questions Java FAQ
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This community-built FAQ covers the “Getting an Item’s Index” exercise from the lesson “Learn Java: ArrayLists”.

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This exercise can be found in the following Codecademy content:

Learn Java

FAQs on the exercise Getting an Item’s Index

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2

I’m positive there are other ways to solve this in one line of code or in just a more concise way but this is my solution for step 8/9:

// Calculate to-dos until case is solved:
    int solveIdx = sherlocksToDos.indexOf("solve the case");
      
    // Change the value printed:
    System.out.println(solveIdx);

something like this would be a one line solution:

System.out.println(sherlocksToDos.indexOf("solve the case"));
3

It should be 4, not 3:

    // Calculate to-dos until case is solved:
    int toDosUntilSolved = sherlocksToDos.indexOf("solve the case") + 1;
      
    // Change the value printed:
    System.out.println(toDosUntilSolved);
4

Actually no, one item in ArrayList is removed before calculating indexOf() :slight_smile:

5 Likes
5

I used the one line solution and it was accepted. But it does seem like we were supposed to use something like your first solution. My question is why we might want to do it the longer way - is there any advantage to it?

6

can I pass in a string name instead of a string to search an array in a list?

7

I have done the 2nd way without even thinking that I need to create a int and it printed me the same answer as codecademy solution. is there a problem if we don’t use int in the code?

8

Ohhh, yes now I see the .remove() above it.