$ perl t.pl

***** Comparing a list of 100 words 10000 times *****

             Rate greparray     array      hash
greparray   997/s        --      -55%      -94%
array      2210/s      122%        --      -86%
hash      16026/s     1507%      625%        --

***** Comparing a list of 1000 words 1000 times *****

            Rate greparray     array      hash
greparray 8.80/s        --      -79%     -100%
array     41.5/s      372%        --      -98%
hash      2070/s    23419%     4887%        --