@classmates = (@classmates, &M1(@n));
Just a quick check reveals:
> perl -lwe'use Benchmark "cmpthese";@a=0..8;cmpthese(-8, {push => sub
+{push@x,@a[0..2]}, comb => sub{@y=(@y,@a[0..2])}})'

Benchmark: running comb, push , each for at least 8 CPU seconds ...
    comb: 28 wallclock secs (28.33 usr +  0.00 sys = 28.33 CPU) @ 44.7
+9/s (n=1269)
    push:  8 wallclock secs ( 8.13 usr +  0.25 sys =  8.38 CPU) @ 4172
+8.04/s (n=349681)
Rate   comb   push
comb  44.8/s     --  -100%
push 41728/s 93056%     --

[download]
I know your arrays aren't growing linearly like this, so the difference wouldn't be so extreme.

  p

In reply to Re: Re: Re: Re: Big Picture by petral
in thread constructing large hashes by duelafn

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