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String Programs
#1
Hi Everyone,

I have just started learning Python on my own. I solved the string exercises given on Google's Python Learning website, https://developers.google.com/edu/python/strings

All the programs have been executed successfully. But as I am new to Python programming, I wanted to know if there is any better way to solve the problems. Please look at the codes below and let me know if you can think of any better way to solve the problems. The codes in red colour are written by me.

-------------------------------------------------------------------------------------------------------------------------

#!/usr/bin/python -tt
# Copyright 2010 Google Inc.
# Licensed under the Apache License, Version 2.0
# http://www.apache.org/licenses/LICENSE-2.0

# Google's Python Class
# http://code.google.com/edu/languages/google-python-class/

# Basic string exercises
# Fill in the code for the functions below. main() is already set up
# to call the functions with a few different inputs,
# printing 'OK' when each function is correct.
# The starter code for each function includes a 'return'
# which is just a placeholder for your code.
# It's ok if you do not complete all the functions, and there
# are some additional functions to try in string2.py.


# A. donuts
# Given an int count of a number of donuts, return a string
# of the form 'Number of donuts: <count>', where <count> is the number
# passed in. However, if the count is 10 or more, then use the word 'many'
# instead of the actual count.
# So donuts(5) returns 'Number of donuts: 5'
# and donuts(23) returns 'Number of donuts: many'
[color=#C0392B]def donuts(count):
    # +++your code here+++
    if count < 10:

        return 'Number of donuts: ' + str(count)
    else:
        return 'Number of donuts: many'
[/color]

# B. both_ends
# Given a string s, return a string made of the first 2
# and the last 2 chars of the original string,
# so 'spring' yields 'spng'. However, if the string length
# is less than 2, return instead the empty string.
[color=#C0392B]def both_ends(s):
    # +++your code here+++
    if (len(s) < 2):
        return ''
    else:
        return s[:2] + s[-2:]
[/color]

# C. fix_start
# Given a string s, return a string
# where all occurences of its first char have
# been changed to '*', except do not change
# the first char itself.
# e.g. 'babble' yields 'ba**le'
# Assume that the string is length 1 or more.
# Hint: s.replace(stra, strb) returns a version of string s
# where all instances of stra have been replaced by strb.
[color=#C0392B]def fix_start(s):
    # +++your code here+++
    testString=s[0]+s[1:].replace(s[0],'*')
    return testString
[/color]

# D. MixUp
# Given strings a and b, return a single string with a and b separated
# by a space '<a> <b>', except swap the first 2 chars of each string.
# e.g.
#   'mix', pod' -> 'pox mid'
#   'dog', 'dinner' -> 'dig donner'
# Assume a and b are length 2 or more.
[color=#C0392B]def mix_up(a, b):
    # +++your code here+++
    testString=b[:2]+a[2:]+' '+a[:2]+b[2:]
    return testString[/color]


# Provided simple test() function used in main() to print
# what each function returns vs. what it's supposed to return.
def test(got, expected):
    if got == expected:
        prefix = ' OK '
    else:
        prefix = '  X '
    print '%s got: %s expected: %s' % (prefix, repr(got), repr(expected))


# Provided main() calls the above functions with interesting inputs,
# using test() to check if each result is correct or not.
def main():
    print 'donuts'
    # Each line calls donuts, compares its result to the expected for that call.
    test(donuts(4), 'Number of donuts: 4')
    test(donuts(9), 'Number of donuts: 9')
    test(donuts(10), 'Number of donuts: many')
    test(donuts(99), 'Number of donuts: many')

    print
    print 'both_ends'
    test(both_ends('spring'), 'spng')
    test(both_ends('Hello'), 'Helo')
    test(both_ends('a'), '')
    test(both_ends('xyz'), 'xyyz')

    print
    print 'fix_start'
    test(fix_start('babble'), 'ba**le')
    test(fix_start('aardvark'), 'a*rdv*rk')
    test(fix_start('google'), 'goo*le')
    test(fix_start('donut'), 'donut')

    print
    print 'mix_up'
    test(mix_up('mix', 'pod'), 'pox mid')
    test(mix_up('dog', 'dinner'), 'dig donner')
    test(mix_up('gnash', 'sport'), 'spash gnort')
    test(mix_up('pezzy', 'firm'), 'fizzy perm')


# Standard boilerplate to call the main() function.
if __name__ == '__main__':
    main()
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#2
Two problems readily present themselves.
1) The code you posted contains formatting, so it cannot be simply copy and pasted for people to examine/try. You should be using a plain text editor or an IDE that supports Python (Python IDE's).

2) The code is written using Python 2.x, as a new Python programmer you should be using and learning Python 3.x, preferably the latest stable version which is 3.6.4.

Quote:...let me know if you can think of any better way to solve the problems.

There usually is, particularly when it comes to people just learning any language. The problem is, with any homework or project is we have no idea as to what you've learned so far and what tools you are allowed to use. The answer to your question may actually result in just confusing you or complicating what is, for now, a straight forward answer. The best way to proceed would be to save your answers, then as your progress, go back and say: "Is this something I can use to make my code better".

Again, I strongly urge you to switch to Python 3 before you proceed further with your studies. I also encourage you to read Pythons style guide PEP 8
If it ain't broke, I just haven't gotten to it yet.
OS: Windows 10, openSuse 42.3, freeBSD 11, Raspian "Stretch"
Python 3.6.5, IDE: PyCharm 2018 Community Edition
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