#4, on the other hand, may have an input with a million integers that would probably make that Java solution, with all its toString calls _and_ string concatenations inside the comparison function that will get called in the ballpark of a billion times, slow down to a crawl.
That's why the proposed solution to #4 is not that of a software _engineer_. An engineer would convert those integers to strings only once. He might keep the concatenations around because they aren't shown to be problematic yet.
I could do this problems fairly easily, but #4 and #5 are harder than they look.
Are you working in Python or Ruby and are good at managing your emotions during interviews -- then you'ld do good. (or might do good).
I would guess there are a number of "qualified" entry level programmers who would struggle to get these done in an hour, especially if you are talking about front end developers or something that is more verbose like Java.
Next step is to print that and show my boss what a privilege it is for him to have me in his team :)
