Python list comprehension fails with syntax error

Question

I was doing excercise no.3 from http://cscircles.cemc.uwaterloo.ca/15b-python-pushups/ , I made the code work but was wondering if it was possible to do it in fewer lines? Here is my solution:

los = [] # short for list of strings
while True:
   s = input()
   if s == '###': break
   los += s.lower().split() # making a list of lower case words from the input     sentences
test = []
for x in los:
   test += str(los.count(x)) # made a new list of the frequency of each word
a = test.index(max(test)) # variable a provides the location of them most frequent word
print (los[a]) # we know the position of the most frequent string, so find it in los.
# a is not needed but it looks neater

So this part in particular is what i'm not happy with:

    for x in los:
       test += str(los.count(x))

I want to re write it like:

test += str(list.count(x)) for x in los

but it tells me invalid syntax..any tips?

Answer 1

I think the syntax you want is:

  # No need for test = []
  test = [str(list.count(x)) for x in los]