BIT Counting: C programming problem

Peter Desnoyers desnoyer at Apple.COM
Thu Jan 12 09:36:59 AEST 1989


In article <35329 at think.UUCP> barmar at kulla.think.com.UUCP (Barry Margolin) writes:
>I haven't seen anyone so far suggest the far end of the time/space
>trade-off: have a 64K table, with each element N containing the number
>...

Note that if disk transfer speed is 1MByte/sec (counting seeks), this
will add 64mS to the total program execution time. If you save 1uS per
call with this table, you need to use the function 64000 times just to
break even. Moral - huge lookup tables are not free - you have to load
them in before you start. (unless you are running from rom :-)

				Peter Desnoyers



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