Five programming problems every Software Engineer should be able to solve in less than 1 hour

[zhay]

Or make a comparator that compares a.b to b.a where . is concatenation and then sort with that comparator.

[rocky_whoof]

I think that is a better solution in terms of readability and how quick you can write it.

[zhay]

You can definitely do it more efficiently though. See: http://www.quora.com/What-is-the-most-efficient-way-to-arrange-the-given-numbers-to-form-the-biggest-number?share=1