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Challenge 1: "Create a script to demonstrate Ackermann function. The
Ackermann function is defined as below, m and n are positive number:
A(m, n) = n + 1 if m = 0
A(m, n) = A(m - 1, 1) if m > 0 and n = 0
A(m, n) = A(m - 1, A(m, n - 1)) if m > 0 and n > 0
eg. A(1, 2) = A(0, A(1, 1))
= A(0, A(0, A(1, 0)))
= A(0, A(0, A(0, 1)))
= A(0, A(0, 2))
= A(0, 3)
= 4
"
My notes:
Clearly described. I seem to recall that the Ackermann function is
tremendously inefficient to calculate recursively, but that memoization
really helps. So, before writing a line of code, I think "use Memoize"
is going to help..
Challenge 2: "Create a script to parse URL and print the components of
URL. According to the Wiki page https://en.wikipedia.org/wiki/URL, the URL
syntax is as below:
scheme:[//[userinfo@]host[:port]]path[?query][#fragment]
eg. jdbc://user:password@localhost:3306/pwc?profile=true#h1
scheme: jdbc
userinfo: user:password
host: localhost
port: 3306
path: /pwc
query: profile=true
fragment: h1
My notes: sounds pretty trivial for regexes, if the lexical syntax of
each component is defined clearly. Ok, reading the above wiki page
doesn't make it 100% clear, but let's hack it up, that's probably good
enough for most cases.
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