I don't know. If you are struggling with A* search, and claiming to be a great programmer, it sound contradictory. I am assuming poster was familiar with graphs and graph searches before he stumbled onto A* search.

Recursive/Non-recursive dfs should be pretty much obvious to a comp sci student. Here is a sample non-recursive dfs:

https://gist.github.com/1789807

A* search is the same, except you change the $graph to include costs, and change the `queue` implementation to pop based on a heuristic function(cost from source till here + cost to dest).

I am not saying a good computer programmer must know A* search - I am saying if you are a programmer, your thought process should be molded in a way you start finding these things obvious.

I can't think of any programmers who I personally know, or otherwise, who aren't well versed in algorithms. Familiarity with algorithms serves 2 purpose:

1. It gives your mind general elasticity and agility.

2. Many times, it gives you foundations on which you build.

I recently wrote this small python lib which converts xml to python dict and vice-versa https://github.com/thoughtnirvana/xmldict. It came naturally to me as I was simply implementing a recursive-descent parser. I don't think had I not known about parsers, the solution would have come naturally to me.

That is just one example. There are other examples involving dynamic programming, counting sort...which translates nicely to real world use cases, and if you don't know the basic algorithms, you end up re-implementing a second-class substitute badly.