Linux command or script counting duplicated lines

Question

If I have a text file with the following conent

red apple
green apple
green apple
orange
orange
orange

Is there a Linux command or script that I can use to get the following result?

1 red apple
2 green apple
3 orange

Answer 1

Send it through sort (to put adjacent items together) then uniq -c to give counts, i.e.:

sort filename | uniq -c

and to get that list in sorted order (by frequency) you can

sort filename | uniq -c | sort -nr

Answer 2

uniq -c file

and in case the file is not sorted already:

sort file | uniq -c

Answer 3

Try this

cat myfile.txt| sort| uniq

Answer 4

Almost the same as borribles' but if you add the d param to uniq it only shows duplicates.

sort filename | uniq -cd | sort -nr

Answer 5

To just get a count:

$> egrep -o '\w+' fruits.txt | sort | uniq -c

      3 apple
      2 green
      1 oragen
      2 orange
      1 red

To get a sorted count:

$> egrep -o '\w+' fruits.txt | sort | uniq -c | sort -nk1
      1 oragen
      1 red
      2 green
      2 orange
      3 apple

EDIT

Aha, this was NOT along word boundaries, my bad. Here's the command to use for full lines:

$> cat fruits.txt | sort | uniq -c | sort -nk1
      1 oragen
      1 red apple
      2 green apple
      2 orange

Answer 6

cat <filename> | sort | uniq -c