Consider a tape containing a block of n strokes, followed by a space, followed by a block of m strokes, followed by a space, followed by a block of k strokes, and otherwise blank. Design a Turing machine that when started on the leftmost stroke will eventually halt, having neither printed nor erased anything $...($a$)...$ontheleftmoststrokeofthesecondblock.$($b$)...$ontheleftmoststrokeofthethirdblock.