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Workshop

Quiz

1:	Given the following code, what's left in `@A` afterward: @A=qw(oats peas beans); shift @A; push @A, "barley"; pop; `oats peas beans` `beans barley` `peas beans barley`
2:	What does `printf("%18.3f", $a)` do? It prints a floating-point number that is 18 characters wide, 15 to the left and 3 to the right of the decimal point. It prints a floating-point number 18 characters to the left of the decimal, a decimal point, and then 3 more digits. It prints a floating-point number that is 18 characters wide, 14 to the left and 3 to the right of the decimal point.
3:	If `tr/a–z/A–Z/` is run against a string, will `tr/A–Z/a–z/` restore the string to its original form? Yes, of course Probably not

Answers

A1:	c. The `shift` removed `oats,` and the `push` added `barley` to the end. The final `pop` was a ruse: No array was specified, so it popped something from the array `@_,` which causes nothing to happen to `@A.`
A2:	c. If you guessed a, you didn't count the decimal point, which occupies a position in the total (18=14+1+3).
A3:	b. The string `"Rosebud"` transformed by `tr/a-z/A-Z/` becomes `"ROSEBUD".` Trying to transform it back with `tr/A–Z/a–z/` yields `"rosebud"—`not the original string.

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