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WORKING WITH FILES
Problem:
Given: A file containing at most 1000 lines.
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Return: A file containing all the even-numbered lines from the original file. Assume 1-based numbering of lines.
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Sample Dataset:
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Bravely bold Sir Robin rode forth from Camelot
Yes, brave Sir Robin turned about
He was not afraid to die, O brave Sir Robin
And gallantly he chickened out
He was not at all afraid to be killed in nasty ways
Bravely talking to his feet
Brave, brave, brave, brave Sir Robin
He beat a very brave retreat
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Sample Output:
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Yes, brave Sir Robin turned about
And gallantly he chickened out
Bravely talking to his feet
He beat a very brave retreat
Solution:
Since genetic data is often stored in files, being able to work with files effectively is essential. Here's a useful tutorial getting into the nitty gritty of files.
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First the file is accessed, in the read mode, and stored into a variable using the open method:
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< >
file = open("input.txt", "r")
Then using the readlines() method, the file is read line-by-line and each odd line is stored into a list variable called lines, then all the list items are joined and printed:
< >
file = open("input.txt", "r")
lines = file.readlines()[1::2]
print("".join(lines))
Output:
Yes, brave Sir Robin turned about
And gallantly he chickened out
Bravely talking to his feet
He beat a very brave retreat
Copy and paste the output you get from running your code on the sample data onto the Rosalind answer terminal and submit. Annnd get yourself a cookie!