ww: how can you change the stograge style of a data structure?
and whenever it comes to efficiency, i dnt think that programmer effort is taken into picture.
I have always taken efficiency as cpu and time consumption
storage? any one of many compression techniques. Think '.zip' or RLE or bit vectors or ....
efficiency? Your usual choices are usually valid, but would you consider them the best measure of the "efficiency" of producing a one-off or rarely used program? Being concerned solely with "cpu and timeUpdate1 consumption" and ignoring "programmer time" might be a serious case of premature optimization.
Update 1: I assume from context that the "time" reference meant "run time."