Newbie data structes question

Diez B. Roggisch deets_noospaam at web.de
Thu Dec 4 15:21:56 CET 2003


> What data structures and flow controls are most appropriate?  Any neat
> flow control in python?

This should do the counting and sorting

def cmp(m1, m2):
  if m1[1] < m2[1]:
    return -1
  elif m1[1] > m2[1]:
    return 1
  return 0

# you can create your own file here
in_file = sys.stdin
lines = in_file.realines()
# sorts the lines in place
lines.sort()

res = {}
for line in lines:
  if res.has_key(line):
    res[line] += 1
  else:
    res[line] = 1

res = res.items()
res.sort(cmp)

res now has this form:

[('brazil', 20), ('cross roads', 0)]

Thats it. In python, you have basically three data structures - tuples
(1,2,3), lists [1,2,3] and dicts {'key' : 'value', 'key2', 3}

You don't have to declare any of them :)

Regards,

Diez




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