$ cat a.out
advanceadvancebox box box
cow
Remove duplicate lines
$ uniq a.out advance box
Count Number of Occurrence
$ uniq -c a.out
2 advance
3 box
1 cow
Print out duplicate lines
$ uniq -d a.out advance box
$ cat a.out
advanceadvancebox box box
cow
Remove duplicate lines
$ uniq a.out advance box
Count Number of Occurrence
$ uniq -c a.out
2 advance
3 box
1 cow
Print out duplicate lines
$ uniq -d a.out advance box
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