This was supposed to be posted last night, but I was trying to make it work properly. This problem reproduces a few Python division problems and took me some time to figure it out. Actually I only knew about this when I checked the winner’s solution (also written in Python).

Without the “gotcha”, the problem is quite easy to solve, if you know how to work with feet and inches. As a metric system native, it was my first time. 😀 It’s called Baby Height, and it says, yo!

Every parent wants to know how tall their child will grow.

Dr. Spaceman’s algorithm, which we describe below

Accurately calculates, with errors very low,

Adult height of any child, with just genetics, yo!

Take the mother’s height and add it to the father’s height.

For a girl, subtract five inches; this I will highlight.

For a boy, you add five inches, or it won’t be right.

Then divide by two, and get your target in plain sight.Dr. Spaceman is convinced that target is precise.

Plus or minus four, in inches, truly will suffice.

When a parent asks the question, looking for advice,

Dr. Spaceman’sanswer is this range, and it’s concise.

Also, a minor problem gotcha is found on the Output rules:

## Output

For each test case, output one line containing “Case #x:

AtoB“, where x is the case number (starting from 1),Ais the smallest andBis the largest baby height, according to Dr. Spaceman’s algorithm.If the algorithm produces a range whose endpoints fall on fractional inches, your program should shrink the range until both endpoints can be expressed in whole inches.

I’ve overlooked that at first. 😛 Anyway, here’s the final code, validated:

from __future__ import division #Get python3 revised division operator def asInches(strFeetInches): #Function converting Foot/inches string to inches nums = strFeetInches[:-1].split("\'") #Split string on ' and remove " marks return int(nums[0])*12 + int(nums[1]) #1 foot = 12 inches, convert for case in range(1,int(raw_input())+1): #For all test cases vector = [] boy = False father = -1 mother = -1 for i in raw_input().split(" "): #Split the case values by spaces if i == "B": #Is it a boy? boy = True elif i == "G": #Is it a girl? boy = False elif father == -1: #If father is not yet known, get it father = asInches(i) #Store his height in inches else: #Father is known, so get mother this time mother = asInches(i) #Store in inches height = (mother + father + (5 if boy else -5))/2 #Baby height math inc = 4.0 #Range default value lower = height-inc #Get lower range if lower != int(lower): #If number is a fraction lower += 0.5 #Reduce range size higher = height+inc #Get higher range if higher != int(higher): #If number is a fraction higher -= 0.5 #Reduce range size print "Case #%d: %1d'%1d\" to %1d'%1d\"" % (case, lower/12, lower%12, higher/12, higher%12)

This problem represents what CodeJam is about. Not only knowing how to code, but also knowing about programming “gotchas” and avoiding them.

Happy jammin’!