perl to delete consecutive duplicate lines

Question

I want to delete the consecutive duplicate lines. i.e. for example

**test.txt**
car
speed is good
bike 
slower than car
plane
super fast
super fast
bullet train          


        

Answer 1

Why don't you just use uniq?

uniq file.txt

Results:

car
speed is good
bike 
slower than car
plane
super fast
bullet train 
super fast

You can also do this with awk:

awk 'line != $0; { line = $0 }' file.txt