A Common-Sense Guide to Data Structures and Algorithms, Second Edition, 2nd Edition

Password Cracker

You’re a hacker (an ethical one, of course) who’s trying to figure out someone’s password. You decide on a brute-force approach, and write some code that produces every possible string of a given length. Here’s the code you whipped up:

def every_password(n)
  (("a" * n)..("z" * n)).each do |str|
    puts str
  end
end

The way this works is you pass in a number to the function, which becomes the variable n.

If n is 3, for example, the code "a" * n produces the string "aaa". The code then sets a loop between all possible strings within the range of "aaa" and "zzz". Running this code will print:

aaa
aab
aac
aad
aae

...

zzx
zzy
zzz

If n is 4, your code will print all possible strings of length 4:

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