Re: Bidirectional lookup algorithm? (Updated: further info.)

[shmem]

Since your strings and integers are unique - why don't you use a hash for strings and an array for integers

#!/usr/bin/perl -l

my %str2int;
my @int2str;

$i=0;
for ('aaaa'..'zzzz') {
    $str2int{ $_ } = ++$i;
    $int2str[$i] = $_;
}

and look up the strings by index into the array, and the integers by key into the hash?

[Laurent_R]

The integers are 64-bits. I do not know what they really look like, but there is clear danger of ending up with a sparse array growing to be much much larger than the hash.

[shmem]

Right you are.

qwurx [shmem] ~/comp/perl/tmp > perl -le '@a = 2**64; for(1..29){$a[2*
+*$_]=$_}print `ps -o vsz= -p $$`'
Out of memory!

Having 8 GB RAM. 2**28 doesn't die.