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can only concatenate list (not "int") to list?
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can only concatenate list (not "int") to list?
#1
I can do:
[1, 2, 3] + [4, 5, 6]
But I cannot do:
nums=[1, 2, 3]
nums[1:]+nums[0]
TypeError: can only concatenate list (not "int") to list


Why?
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#2
see: http://c4m.cdf.toronto.edu/cohort1/winte...tions.html

Specifically In [4]:

not with a slice, but same thing.

essentially nums[0] is considered an int, not a list
concatenate must be list + list, not list + int

so the following works:
n = [1,2,3,4,5]
n1 = n[3:]+n[4:]
print(n1)
Reply
#3
(Jan-17-2017, 05:38 AM)Larz60+ Wrote: n = [1,2,3,4,5]
n1 = n[3:]+n[4:]
print(n1)

Thanks. I tried out a better way:nums[1:]+[nums[0]]
Reply


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