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+--- Thread: len function - (/thread-14892.html)
len function - - jojotte - Dec-22-2018
Hey!
I am trying to do the following:
1/user inputs a name e.g. "John".
2/user gets returned with the last character of the string e.g. "n".
Where I am so far:
name = input("provide an example of name: ")
indexOfName = len(name)
lastLetterofName = name[indexOfName]
print(lastLetterofName)This does not work. I get IndexError: string index out of range
However, this works (see line 3):
name = input("provide an example of name: ")
indexOfName = len(name)
lastLetterofName = name[indexOfName - 1]
print(lastLetterofName)Any idea what I got wrong?Thanks!
RE: len function - - ichabod801 - Dec-22-2018
Python is what is called 0-indexed. The index of the first item in a list or string is 0. Thus the index of the last item is len(list_or_str) - 1.
RE: len function - - jojotte - Dec-22-2018
Thanks for this.
However when I specifically print indexOfName I get 4 if, say, the name I input is John...?
name = input("provide an example of name: ")
indexOfName = len(name)
print(indexOfName)
lastLetterofName = name[indexOfName - 1]
print(lastLetterofName)
RE: len function - - ichabod801 - Dec-22-2018
Right. indexOfName is the result of len(name), which is the number of items in the sequence (letters in the string). So that is 4, since there are four letters in John. The len function gives the length, not the index of the last character. Those, as you have seen, are two different things.
RE: len function - - jojotte - Dec-22-2018
OK, brilliant, makes sense!
Ta!
RE: len function - - buran - Dec-22-2018
If you don't know, python supports also negative indexes
name = input("provide an example of name: ")
print(name[-1])