didn't see a sprintf solution...

#!/usr/bin/perl
use strict;

my @num = ( "000006", "00005.55", "0004.5650");

foreach (@num) {
    print $_, " becomes: ";
    print sprintf("%d\n", $_);
}
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which produces....

000006 becomes: 6
00005.55 becomes: 5
0004.5650 becomes: 4
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