str.isalpha() : checks whether the string consists of alphabetic characters only.
str.isdigit() : checks whether the string consists of digits only.
str.center(width, fillchar) : returns centered in a string of length width. Padding is done using the specified fillchar. Default filler is a space.
def main():
s = input('Please enter a digit: ')
l = [int(s), int(s.center(2,s)), int(s.center(3,s)), int(s.center(4,s))]
total = sum(l)
print(int(s))
print(l)
print(total)
Result:
=============================exercise15.py =============================
Please enter a digit: 9
9
[9, 99, 999, 9999]
11106
>>>
=============================exercise15.py =============================
Please enter a digit: 1
1
[1, 11, 111, 1111]
1234
>>>
str.startswith()： checks whether the string starts with str, optionally restricting the matching with the given indices start and end.
Parameters：
str− This is the string to be checked.
beg− This is the optional parameter to set start index of the matching boundary.
end− This is the optional parameter to set start index of the matching boundary.
Return Value
This method returns true if found matching string otherwise false.
'delimiter'.join(seq): The join()method returns a string in which the string elements of sequence have been joined by str separator/delimiter.
>>> delimiter=''
>>> seq=['list1']
>>> seq2=['list2']
>>> delimiter.join(seq+seq2)
'list1list2'
>>> seq+seq2
['list1', 'list2']
Slicing and Reverse of string:
