Demo/comparisons/sortingtest.py
#! /usr/bin/env python # 2) Sorting Test # # Sort an input file that consists of lines like this # # var1=23 other=14 ditto=23 fred=2 # # 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. # # fred=2 other=14 ditto=23 var1=23 # # Lines may be up to several kilobytes in length and contain # zillions of variables. # This implementation: # - Reads stdin, writes stdout # - Uses any amount of whitespace to separate fields # - Allows signed numbers # - Treats illegally formatted fields as field=0 # - Outputs the sorted fields with exactly one space between them # - Handles blank input lines correctly import re import sys def main(): prog = re.compile('^(.*)=([-+]?[0-9]+)') def makekey(item, prog=prog): match = prog.match(item) if match: var, num = match.groups() return int(num), var else: # Bad input -- pretend it's a var with value 0 return 0, item for line in sys.stdin: items = sorted(makekey(item) for item in line.split()) for num, var in items: print "%s=%s" % (var, num), print main() |