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surfers with their scores

Code Magnets Solution

You were to rearrange the code magnets at the bottom of the page
to complete the program shown below. Rather than using two
arrays, this program stores the results from the surfing contest in a
hash:

You need to start with an empty hash,
as opposed to an empty array.

scores = {}

result_f = open("results.txt")
for line in result_f:
(name, score) = line.split()
After splitting out the name and the score, use
scores[score] = name the value of “score" as the key of the hash and

result_f.close() the value of “name" as the value.
You'll find out soon why the “score"
Use a for loop print("The top scores were:") and not the “name" is used (in this
case) as the key of the hash.
to process the for each_score in scores.keys():
contents of
the hash. print('Surfer ' + scores[each_score] + ' scored ' + each_score)

Display each row from the hash,
describing the association.

Q: Can I append data to a hash just like I did with an array? Q: Can I use anything as the key of a hash?

A: Yes, and no. There’s no append() method for hashes A: No, you can’t. The rules Python applies here can be complex
like the one included with every array. To add a new row of (as they can be in other programming languages, too). The best
data to an existing hash, use code similar to that used in the advice we can give you is to stick with numbers and strings as
solution, above. Hashes do have their own set of methods, but keys. Trust us: this isn’t as restrictive as it first sounds and is, by
append() is not one of them. far, the best/easiest strategy to follow.

156 Chapter 5