Exercises
See Appendix A for answers to the following exercises:
Remember, it’s normal to be surprised by some of the things that regular expressions do. That’s one reason the exercises in this chapter are more important than the others. Expect the unexpected.
[10] Make a program that prints each line of its input that mentions
fred
. (It shouldn’t do anything for other lines of input.) Does it match if your input string isFred
,frederick
, orAlfred
? Make a small text file with a few lines mentioning “fred flintstone” and his friends. Then use that file as input to this program and the ones later in this section.[6] Modify the previous program to allow
Fred
to match as well. Does it match now if your input string isFred
,frederick
, orAlfred
? (Add lines with these names to the text file.)[6] Make a program that prints each line of its input that contains a period (
.
), ignoring other lines of input. Try it on the small text file from the previous exercise: Does it noticeMr. Slate
?[8] Make a program that prints each line with a word that is capitalized but not ALL capitalized. Does it match
Fred
but neitherfred
norFRED
?[8] Extra credit exercise: Write a program that prints out any input line that mentions both
wilma
andfred
.
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