O(sqrt N). "." -> black ===== fact is I've never seen a needle longer than 25 bits ===== after tremendous reduction -> not an evangelist but rather opposit ===== => done again only grid and needle plus where we are & where to go witout landmarks no obstacles, walls, nor corridors ===== eps 150x150 -> 150 x150 needle is located here and walk starts at the center of the grid this is a trace after 150 x 150 steps ===== => done analytical -> optimul ... which issupposed to cover all cells in the grid but because of bisit to one cells multiple times... it seems ===== e.g. 100111001111 => done ===== if the randomwalk is lucky more or less this is an example of such an lucky random walk N(p17) note that when n=1 simple needlke << maximize << a needle ===== => done royal-road x2 ===== note that n=1... simply a needle search p19 ===== => done where we are ? from landmarks ==== it is this benchmark i want to propose here to chalenge trhe community ===== note that n=1... simply a needle search p19