title: Regular expression with even sum of a's and b's
body: <p>Hello I've browser a trivia site about cs and one of the question was to construct a regular expression with two digits eg (1,0) that generate strings that have even number of 0's and 1's. To be clearer if we had m 1's and n 0's then m+n should be even. Can there exist such a regular expression? I've been brainstorming for a while and I cannot find any regex to match this.</p>