Failed another programming intervie. Didn't expect the 2D array question. Feel so bad. Just wanna cry and give up. I need to get better..fast.

Better at what? You can't and will never be good at every aspect.

True

At university the IT class with the highest failure rate was the 2nd year class "Algorithms and datastructures".

Once you know it it seems obvious, but learning it takes time as well as a deep understanding of multiple layers of abstractions.

Hell, I know lots of developers who after years working still don't understand a lot of the intricacies of data structures.

On the other hand: If it does click (and it will eventually if you really keep at it), it really sticks because you can only know it by truly understanding it.

@brahn I was great at algorithms. What kicked my ass was Computer Architecture. Failed that class 3 times. Fucking pipeline stalls.

On the plus side, after taking it three times I totally get it now :P

Maybe they suck at entrance tests. If they value someone who doesn't need to look up the docs more than someone who'll learn quickly and work smart, maybe you've dodged a bullet.

Don't beat yourself up too hard. Study up a bit and move on.