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Re:Ask HN: Got a CS degree, but I’m unable to be programmer.... by generallyfalse on Monday July 23, 2018 @05:22PM (#17596143)
This is what I tried, recursion taking care of puting the simplest cases first. I haven't checked the solution. I think this kind of problem is like a state machine. In each call of the recursion the length of the pattern or the lengh of the string should decrease, so finally one get to the easy cases of length in (0,1,2).

This kind of problems are designed to test you can define a grammar and apply recursion. Another problem with the same flavor could be to evaluate string expressions like "3+25" using a grammar. My one-hour solution (not checked). But I think I have done similar problems.

         def pat(s,p):
    ...:     if s == "":
    ...:         if len(p)>1 and p[1] in "?*":
    ...:             return pat(s,p[2:])
    ...:     if p == "": return s == p
    ...:     if len(p) == 1:
    ...:         if p == "*": return True
    ...:         return s == p
    ...:     if len(p) == 2:
    ...:         if p[1] == "?":
    ...:             return s == p[0] or s==""
    ...:         if p[1] == "*":
    ...:             if s[0] != p[0]: return False
    ...:             if s == p[0]: return True
    ...:             return pat(s[1:],p)
    ...:     if p[1] != "?" and p[1] != "*":
    ...:         return s[0] == p[0] and pat(s[1:],p[1:])
    ...:     if p[1] == "?":
    ...:         if (s[0] != p[0]):
    ...:              return pat(s,p[2:]))
    ...:         if (s[0] == p[0]):
    ...:             return pat(s[1:],p[2:]) or pat(s,p[2:])
    ...:     if p[1] =="*":
    ...:         if (s[0] != p[0]): return pat(s,p[2:])
    ...:         return pat(s[1:],p) or pat(s,p[2:])
    ...:
    ...:
Re:Ask HN: Got a CS degree, but I’m unable to be programmer.... by Tmp1234 on Monday July 23, 2018 @07:54PM (#17597011)
Your solution looks better than mine. Is there anything you've gleaned from the leetcode examples I posted?
Re:Ask HN: Got a CS degree, but I’m unable to be programmer.... by generallyfalse on Tuesday July 24, 2018 @10:53AM (#17601543)
I see that you prefer not to use recurrency in Python. That decision is correct since python is not optimized for recurrency but it also can make the code more complex. See https://realpython.com/python-thinking-recursively/

On the other hand, using iterators in python is nice. You didn't use iterators to compute the sum of cubes, many problems can be solved in one line using iterators. https://www.datacamp.com/community/tutorials/python-iterator...

Perhaps your code should try to go from the easy cases to the complex cases in pattern matching.

As a hobby programmer I program without stress, if I was to make a living by programming I think I shouldn't enjoy so much.

I think you should read norvig post: http://norvig.com/21-days.html, also to learn to program in python: https://github.com/norvig/pytudes

I believe that in a year or two you could be prepared to judge your progress