Going Deeper with Strings
Read this for more on strings.
len is a built-in function that returns the number of characters in a string:
>>> fruit = 'banana' >>> len(fruit) 6To get the last letter of a string, you might be tempted to try something like this:
>>> length = len(fruit) >>> last = fruit[length] IndexError: string index out of rangeThe reason for the
IndexErroris that there is no letter in ’
banana’ with the index 6. Since we started counting at zero, the six letters are numbered 0 to 5. To get the last character, you have to subtract 1 from
>>> last = fruit[length-1] >>> last 'a'Or you can use negative indices, which count backward from the end of the string. The expression
fruit[-1]yields the last letter,
fruit[-2]yields the second to last, and so on.