Week 10

Question 1

What comes in to the uniq program?

Answer 1

Either stdin or a file. Both treated the same once the file is open

Filename is identified as the sole parameter that uniq might accept

Question 2

What transformations do I need to make to the data in the uniq program?

Answer 2

No changes needed to the data

Question 3

What part of the data is processed right away?

Answer 3

I can print each line of text if it is different from the preceding line

Question 4

What part of the data do I need to keep longer?

Answer 4

I need to remember the last processed line of the file

I need to compare that line with a new line

Question 5

What goes out of the program?

Answer 5

All output to stout. Print each line that isn’t the same as the one before.

Question 6

Uniq program: What assumptions can I make?

Answer 6

Are any given? Zero or one arguments of the program. Problem speaks of lines of the file, so we’ll infer line-based text input.

Question 7

Uniq program: Can I reasonably make any of my own assumptions?

Answer 7

Maximum line length. Set to 80 characters.

All characters will be printable.

Question 8

What constraints exist for uniq program?

Answer 8

Full program in C

Question 9

Are there strange cases to handle in uniq program?

Answer 9

Empty file

One line in the file (so nothing to compare against)

Question 10

What is important for the solution to do for uniq?

Answer 10

Single-pass of the file so hat it can be used with a pipe if necessary.