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Victor Stanciu
Full Stack JavaScript Techdegree Student 11,184 PointsMy solution
This is my solution for the practice:
Match "img_0" followed by a number, then a dot, then either "jpg", "png" or "gif":
img_0\d\.(jpg|png|gif)
Match "pro" followed by either "jec", "trac" or "c" then followed by "tor":
pro(jec|trac|c)tor
Match "img_" followed by either "sm" or "0<and a number>", then followed by either "_0<and a number>" or nothing, then followed by a dot, then followed by either "jpg" or "png":
img_(sm|0\d)(_0\d)?\.(jpg|png)
Match either "www" or "api" followed by a dot, or nothing at all, then followed by either "github" or "teamtreehouse", then followed by a dot then followed by "com":
((www|api)\.)?(github|teamtreehouse)\.com
Hope this helps!
1 Answer

Jason Larson
7,955 PointsI know this lesson was on grouping, but it seems like overkill for numbers 3 and 4. For number 3, all the ones to include had "img_" and something, and the one to exclude didn't have an underscore, so img_.+
works for the given test cases. Again, with number 4, all the grouping seems like overkill, as the ones to be excluded end in ".net" and the ones to match end in ".com", so .+\.com$
gets all but the ones ending in ".net". It would be nice if they gave more explicit details on what to match and exclude, and/or gave broader test sets.
Victor Stanciu
Full Stack JavaScript Techdegree Student 11,184 PointsVictor Stanciu
Full Stack JavaScript Techdegree Student 11,184 PointsHi Jason Larson!
Your solution is clearly better! Thank you for sharing!