> Answering the question was a little tedious and subject to my tired human eyes making no mistakes Who would do this manually? Concatenate the two lists and

> Answering the question was a little tedious and subject to my tired human eyes making no mistakes Who would do this manually? Concatenate the two lists and sort them. Use "uniq -c" to count the duplicate lines and grep to pull out the lines which occur twice. It would take a few seconds.