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Problems with arrays & for loops

Karl Davies

Joined: Sep 21, 2010
Posts: 6
Hello! I'm incredibly new to Java and programming. The problem I'm having with this piece of code is the marked for loop (or at least I think it is), I want it to take all all elements below 10 and copy them into array10 but it just isn't doing that and I'm not sure where I've gone wrong. Help would be brilliant Thanks.

Joanne Neal

Joined: Aug 05, 2005
Posts: 3742
In your MARKED for loop, x is not the value of an array element - it's the index of an array element. The value is represented by randArray[x].

Also, you don't need to use system.arraycopy to copy a single array element. Just use

And just for the record, your parameters to System.arraycopy are wrong. The last parameter is the number of values to copy, so the first time round the loop you copied none, the second time one, the third time two, etc

Karl Davies

Joined: Sep 21, 2010
Posts: 6
Brilliant! It's in working order now, thank you Joanne!
Wouter Oet
Saloon Keeper

Joined: Oct 25, 2008
Posts: 2700

Why not create a 2D array?

"Any fool can write code that a computer can understand. Good programmers write code that humans can understand." --- Martin Fowler
Please correct my English.
Campbell Ritchie

Joined: Oct 13, 2005
Posts: 46362
And welcome to the Ranch
I agree. Here's the link:
subject: Problems with arrays & for loops
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