Click here to navigate the course.

Drag the edges to resize the window.

In Projects, you can keep track of your progress as you go throught the tasks. Check each item as you complete it!

$ uniq deserts.txt

uniq stands for "unique" and filters out adjacent, duplicate lines in a file. Here uniq deserts.txt filters out duplicates of "Sahara Desert", because the duplicate of 'Sahara Desert' directly follows the previous instance. The "Kalahari Desert" duplicates are not adjacent, and thus remain.

$ sort deserts.txt | uniq

A more effective way to call uniq is to call sort to alphabetize a file, and "pipe" the standard output to uniq. Here by piping sort deserts.txt to uniq, all duplicate lines are alphabetized (and thereby made adjacent) and filtered out.

sort deserts.txt | uniq > uniq-deserts.txt

Here we simply send filtered contents to uniq-deserts.txt, which you can view with the cat command.

report a_bug
If you see a bug or any other issue with this page, please report it here.