| #! /usr/bin/env python
|
|
|
| # 2) Sorting Test
|
| #
|
| # Sort an input file that consists of lines like this
|
| #
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| # var1=23 other=14 ditto=23 fred=2
|
| #
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| # such that each output line is sorted WRT to the number. Order
|
| # of output lines does not change. Resolve collisions using the
|
| # variable name. e.g.
|
| #
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| # fred=2 other=14 ditto=23 var1=23
|
| #
|
| # Lines may be up to several kilobytes in length and contain
|
| # zillions of variables.
|
|
|
| # This implementation:
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| # - Reads stdin, writes stdout
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| # - Uses any amount of whitespace to separate fields
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| # - Allows signed numbers
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| # - Treats illegally formatted fields as field=0
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| # - Outputs the sorted fields with exactly one space between them
|
| # - Handles blank input lines correctly
|
|
|
| import re
|
| import sys
|
|
|
| def main():
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| prog = re.compile('^(.*)=([-+]?[0-9]+)')
|
| def makekey(item, prog=prog):
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| match = prog.match(item)
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| if match:
|
| var, num = match.groups()
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| return int(num), var
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| else:
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| # Bad input -- pretend it's a var with value 0
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| return 0, item
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| for line in sys.stdin:
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| items = sorted(makekey(item) for item in line.split())
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| for num, var in items:
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| print "%s=%s" % (var, num),
|
| print
|
|
|
| main()
|
