Shorthand for any character
[.] not the same as .
19/03/2022 19-03-2022 // matches both
Shorthand for any character is .
: "Shorthand for any character
Remember that metacharacters are different inside and outside a class
[-./] more precise, [.] not the same as .
echo $A | grep '19[-./]03[-./]2022' -o | tee result.txt
echo $B | grep '19[-./]03[-./]2022' -o | tee result.txt -a
echo $C | grep '19.03.2022' -o | tee result.txt -a