Given an ArrayList a , write an expression that refers to the first element of the ArrayList. So, if the array a held the following values: 33,14,97,265, 84, then the value of your expression should be 33.
I tried:
Object obj = arrayList.get(33);
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I am having a hard time with my code
Given an ArrayList a , write an expression that refers to the first element of the ArrayList. So, if the array a held the following values: 33,14,97,265, 84, then the value of your expression should be 33.
I tried:
Object obj = arrayList.get(33);
Related threads:
Re: I am having a hard time with my code
Check out the API for ArrayList. The get(int) function returns the value at that index. Index 33 doesn't exist.
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Re: I am having a hard time with my code
.get(int) refers to the Arraylist index, not the value of the ArrayList object.
Note:
ArrayList indices start off from 0, just like arrays.
Edit: Too slow
Last edited by newbie; November 12th, 2011 at 09:32 AM.
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Re: I am having a hard time with my code
I do not understand.
Re: I am having a hard time with my code
Try thinking -.-
Now, with what I also said in mind, what index would your value '33' correspond to?The get(int) function returns the value at that index
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Re: I am having a hard time with my code
Object obj = arrayList.get(33);
I tried that and it did not work. I feel completely lost.
Re: I am having a hard time with my code
An ArrayList which contains values: 2, 4, 6, 8 has a size of 4.
get(int) method returns the value @ the specified index.
ArrayList indices start from 0.
In this case, all the indices will range from 0:3.
Can't make it clearer without coming to your house and making Kevin's cat type it for you
Oh yeah: be sure to check out Oracle's Java Tutorials - starting with the basics.
Last edited by newbie; November 11th, 2011 at 08:03 PM.
Please use [highlight=Java]//code goes here...[/highlight] tags when posting your code
Re: I am having a hard time with my code
Thanks, I guess I'm a bit slow because I still do not understand. I appreciate your time and response. I am new in this class and your respnse is so foreign to me. I am in desperate need of a tutor and am trying my hardest to complete this question as well as understand what I am doing. Have a great day/night.
Re: I am having a hard time with my code
Like newbie said, if you're in that dire of straits, you need to start at the basic tutorials.
And my cat is not helpful when it comes to keyboards or mice.
stanleyMouse.jpg
See?
Useful links: How to Ask Questions the Smart Way | Use Code Tags | Java Tutorials
Static Void Games - Play indie games, learn from game tutorials and source code, upload your own games!
Re: I am having a hard time with my code
I guess everyone understand but me. First and foremost, I am allergic to cats, secondly, please pardon me if I don't get the joke, all I know is that my professor is located in Germany and I am alone in this sinking ship, be well.
Re: I am having a hard time with my code
.get() gets the element referenced by the index. You're putting the value into get(), not the index.
In you array you have the following:
index: value
0: 33
1: 14
2: 97
3: 265
4: 84
What is the index of the first item? Hint: it's not 33.
Re: I am having a hard time with my code
The index of the first value would be zero right?
Re: I am having a hard time with my code
yep (or you can try it out and see).
Re: I am having a hard time with my code
|32|12|31|33|
Let's say it's an array named Arr.
It's size is 4, why? Coz it has four elements(Values) in it.
How do you get values? Like;
Arr[0]; this will be 32
Arr[1]; this will be 12
And what if you will try to do;
Arr[33]; As 33 index doesn't exist, why this index doesn't exist? Coz your array size is only 4, so it makes it's index limited to 0:3. Now this statement will throw ArrayOutOfBoundException.
I don't know if you still catch this or not else invite us at home to teach you in much better wayKidding
Re: I am having a hard time with my code
Haha!Originally Posted by KevinWorkman
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