RegEx Flashcards
1
Q
What file header do you need for RegEx
A
include <regex></regex>
2
Q
What symbols are used to represent a set or a range
A
Square brackets [set/range]
3
Q
What symbol represents a repeating pattern
A
The plus sign +
4
Q
How do you represent a backslash (for c++)
A
Four escape sequences \\
5
Q
What version of c++ supports raw string literals
A
11
6
Q
What is the syntax of raw string literals
A
Use quotes after an R, like R”" for a single \ char
7
Q
Only match beginning of line
A
8
Q
Any character between pattern
A
.
9
Q
Any character starting or ending
A
?
10
Q
Repeat exactly x times
A
{x}
11
Q
Repeat at least x times
A
{x,}
12
Q
Repeat between x and y times
A
{x,y}
13
Q
What are the 6 equivalent class names for a regular expression
A
- [[:upper:]] = [A-Z]
- [[:lower:]] = [a-z]
- [[:digit:]] = [0-9]
- [[:alnum:]] = [0-9a-zA-Z]
- [[:space:]] = space or tab
- [[:alpha:]] = [a-zA-Z]
14
Q
What is the negation option for grep
A
-v (for inVerted)
15
Q
What are the 9 sort options
A
- -c (already sorted?)
- -m (merge sorted files)
- -u (only unique lines)
- -o (output file, same as >)
- -b (ignore leading blanks)
- -n (numerical)
- -t (delimiter)
- -r (reverse)
- +/-n (begin/ignore field number)
