evandrix · August 17, 2011 00:36
diff --git a/1-city_grid.txt b/1-city_grid.txt
 This grid shows the restaurants in Hamburg which have E la Carte units ("Prestos") installed in
 them. The Ps in the grid represent restaurants with Prestos installed ("Prestorants"). Os
 represent restaurants without prestos.

 Alyssa P. Hacker from the E la Carte ops team wants to count the number of restaurants in the
 largest contiguous rectangular block of Prestorants. What is the number that she comes up with?

 Answer: __44__

 top-left corner:     (15, 5742)
 bottom-right corner: (18, 5752)
 ...where (0,0) is top-leftmost corner; right-down are positive x-y directions
diff --git a/2-bloom_filter.txt b/2-bloom_filter.txt
 Chef Claudio loves to have food specials but likes knowing what each day's specials are to be a
 challenge. So, he assigns a random 3-digit alphanumeric code to each of the 250 items he might
 make and publishes this list. Each day, he chooses a set of five items to make and uses a grid
 with a square for each of the 36 letters/numbers to let guests know if a particular item they
 want is a special that day. To do this, for each of the digits of each item, he crosses out that
 square on the grid (if the square is already crossed out, he makes no change).

 What is the probability (to the ten-thousandths place) that a guest chooses an item and the grid
 makes it appear to be today's special when in fact it is not?

 Answer: (1-(1-1/36)^(15))^3 -> 0.0409 [parameters: k=3; n=5; m=36]

 What is the probability (to the ten-thousandths place) that a guest chooses an item and the grid
 makes it appear to be unavailable as today's special when in fact it is available?

 Answer: 0 (false negatives not possible)

 data:image/gif;base64,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%3D
diff --git a/challenge3.txt b/challenge3.txt
 rot13 is an ancient encryption scheme that is notably not very secure. The basic idea is that
 you assign each letter a number (a =0, b = 1, c = 2, ... ). Then you have some value that you
 'rotate' the numbers on... essentially adding to the initial letter's value modulo the total
 number of letters. Example: b with a rotation of 12 is ( (1 + 12) % 26 ) = 13.

 Assume that your program has an encrypted message (that has the spaces originally removed) as
 input, as well as a large dataset in the original language (i.e. a book worth of text). How
 would you decode the encrypted message (find out what the rotation number is) including
 re-inserting the spaces?
	This grid shows the restaurants in Hamburg which have E la Carte units ("Prestos") installed in
	them. The Ps in the grid represent restaurants with Prestos installed ("Prestorants"). Os
	represent restaurants without prestos.

	Alyssa P. Hacker from the E la Carte ops team wants to count the number of restaurants in the
	largest contiguous rectangular block of Prestorants. What is the number that she comes up with?

	Answer: __44__

	top-left corner: (15, 5742)
	bottom-right corner: (18, 5752)
	...where (0,0) is top-leftmost corner; right-down are positive x-y directions
	Chef Claudio loves to have food specials but likes knowing what each day's specials are to be a
	challenge. So, he assigns a random 3-digit alphanumeric code to each of the 250 items he might
	make and publishes this list. Each day, he chooses a set of five items to make and uses a grid
	with a square for each of the 36 letters/numbers to let guests know if a particular item they
	want is a special that day. To do this, for each of the digits of each item, he crosses out that
	square on the grid (if the square is already crossed out, he makes no change).

	What is the probability (to the ten-thousandths place) that a guest chooses an item and the grid
	makes it appear to be today's special when in fact it is not?

	Answer: (1-(1-1/36)^(15))^3 -> 0.0409 [parameters: k=3; n=5; m=36]

	What is the probability (to the ten-thousandths place) that a guest chooses an item and the grid
	makes it appear to be unavailable as today's special when in fact it is available?

	Answer: 0 (false negatives not possible)

	data:image/gif;base64,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%3D
	rot13 is an ancient encryption scheme that is notably not very secure. The basic idea is that
	you assign each letter a number (a =0, b = 1, c = 2, ... ). Then you have some value that you
	'rotate' the numbers on... essentially adding to the initial letter's value modulo the total
	number of letters. Example: b with a rotation of 12 is ( (1 + 12) % 26 ) = 13.

	Assume that your program has an encrypted message (that has the spaces originally removed) as
	input, as well as a large dataset in the original language (i.e. a book worth of text). How
	would you decode the encrypted message (find out what the rotation number is) including
	re-inserting the spaces?