Get un common numbers from two files

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1

Hi,
I have two files:

abc :

50040
123123
31703

cde:

104
97
50040
123123
31703
36609
50534

How to get all the numbers from cde which are not in abc?

result must be :
104
97
36609
50534

Thanks for your help.
Jingi

2

sort the files in ascending order then use comm

sort -o abc.srt abc
sort -o cde.srt cde
comm -13 abc.srt cde.srt > resultfile
3

grep -vf abc cde

4

Above one works with /usr/xpg4/bin/grep not with
/usr/xpg4/bin/grep -vf a b
Not this one /usr/bin/grep

Thought will save soe time to others as I went through man to figure this out