working on specific characters in a string in python

Question

I am new to python. I have used c before. There we can work character by character using indexing in string. I was trying to convert the whole string to lower case, reverse it and print it with first character in upper case

first_name = input("enter your first name\n")
last_name = input("enter your last name\n")
first_name = first_name.lower()
last_name = last_name.lower()
def rev(s):
 str = ""
 for i in s:
    str = i + str
    return str
first_name = rev(first_name)
last_name = rev(last_name)
first_name[0].upper()
last_name[0].upper()
print(first_name + " " + last_name)

The output is

enter your first name

Manash

enter your last name

Sharma

m s

Python allows string indexing as well. See this answer for how to reverse a string using Python's string indexing: [https://stackoverflow.com/questions/931092/reverse-a-string-in-python](https://stackoverflow.com/questions/931092/reverse-a-string-in-python) — vielkind, May 04 '18 at 14:46

Rakesh · Answer 1 · 2018-05-04T14:51:11.013

0

You can use [::-1] to reverse your string
str.capitalize or str.title to get the first letter upper case

Demo:

first_name = input("enter your first name\n")
last_name = input("enter your last name\n")
first_name = first_name[::-1].capitalize()
last_name = last_name[::-1].capitalize()

edited May 04 '18 at 14:51

answered May 04 '18 at 14:43

Rakesh

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no need for the `.lower()` call `.capitalize()` handles that – Chris_Rands May 04 '18 at 14:50
@Chris_Rands. Thanks. – Rakesh May 04 '18 at 14:51
But we were asked not to use any library functions. How can we achieve that without library functions. – Manash Sharma May 04 '18 at 19:14
@ManashSharma only default method are used here – Rakesh May 04 '18 at 19:28

L3viathan · Answer 2 · 2018-05-04T22:33:36.877

0

Your mistake lies in returning immediately inside the for loop, and in not assigning the capitalization:

first_name = input("enter your first name\n")
last_name = input("enter your last name\n")
first_name = first_name.lower()
last_name = last_name.lower()
def rev(s):
    str = ""
    for i in s:
       str = i + str
    return str
first_name = rev(first_name)
last_name = rev(last_name)
first_name = first_name[0].upper() + first_name[1:]
last_name = last_name[0].upper() + last_name[1:]
print(first_name + " " + last_name)

Note that there are of course nicer, quicker, and easier ways of doing this, as shown in the other answer.

edited May 04 '18 at 22:33

answered May 04 '18 at 14:45

L3viathan

26,748
2
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File "3.py", line 12, in first_name[0] = first_name[0].upper() TypeError: 'str' object does not support item assignment – Manash Sharma May 04 '18 at 19:11
Oops, you're right. You can't change strings, they are immutable. Fixed answer. – L3viathan May 04 '18 at 22:33

working on specific characters in a string in python

2 Answers2