Verified answer

Capitalizing Second Letters - Python

I will be putting here two programs. Both have their own assumptions of the input and output criteria.

The General Logic is to first take in the user input of a string, convert it into a list of characters, and run through it to capitalize the second letter.

The methods used:

• len(string)

It returns the length of the string passed as parameter

• str.isalpha()

It does not take any parameters. It returns True if all characters in the string str are alphabets, and False if even one of them is not.

We will be checking individual characters with this method.

• str.upper()

This method capitalizes the string str passed to it and returns it.

• str.join(iterable)

This method joins the elements of the iterable (we will be using a list here) with the str string in between.

So, if we had a list

my_list = ['a', 'b', 'c']

And if we want to join them with, say # in between, we would do:

'#'.join(my_list)

This would return "a#b#c"

We can use an empty string so as to join all elements directly without anything in between.

Let's get to the programs.

The First Program - StringFun.py

This program works correctly if no special characters are passed to it, just like in the sample input shown in the question. If any special characters are to be passed, it would misinterpret the second character.

So you have to be pretty restricted in the input.

Here goes the code.

# Python Program to take input from user and

# capitalize second letter of each word

sentence = input("Enter your string: ")  # Taking User Input

# Make a list of characters in the sentence string

characters = [char for char in sentence]

length = len(characters)    # Storing length in a variable

# If the first character is an alphabet, check if second character exists

if characters[0].isalpha():

       if length>1:    # Condition to check if second character exists

               if characters[1].isalpha():  

                       # If second character is an alphabet as well, capitalize it

                       characters[1] = characters[1].upper()

# Run a loop to check for groups of <space><alphabet><alphabet>

# and capitalize the second letter

for i in range(length-2):

   if characters[i] == ' ' and characters[i+1].isalpha() and characters[i+2].isalpha():

       characters[i+2] = characters[i+2].upper()

# Join all the characters

# Nothing is to be inserted between them, hence the empty string ''

newsentence = ''.join(characters)

print(newsentence)      # Print out the new sentence

Screenshots of the code and terminal runs are attached. They are the first two of the four screenshots.

The Second Program - AdvancedStringFun.py

This program assumes the following:

• Space(s) mark(s) a new word
• "Letters" mean Alphabets, so second alphabet should be capitalized
• There may exist any non-alphabets between the first and second one
• If a word has only one alphabet, it cannot be capitalized, regardless of any numbers or other characters (except space) preceding it

This program works pretty well for any case. It covers cases where the first program fails.

Here goes the code.

# Python Program to take input from user and

# capitalize second letter of each word

sentence = input("Enter your string: ")  # Taking User Input

# Make a list of characters in the sentence string

characters = [char for char in sentence]

length = len(characters)    # Storing length in a variable

# We will use two boolean flags

newWord = True

firstLetterReached = False

i = 0

while i < length:       # Outer Loop to run through all characters

       # If newWord is True, search for first letter

       # When first letter is reached, search for second letter and capitalize it

       if newWord:      

               if(firstLetterReached):         # Condition when first letter of word has been found

                       while i < length:

                               # If a space is found, firstLetter was the only letter in the word

                               # Hence, set firstLetterReached to False and break loop

                               if characters[i] == ' ':        

                                       firstLetterReached = False

                                       i += 1

                                       break

                               if characters[i].isalpha():

                                       # When second letter is found, capitalize it

                                       characters[i] = characters[i].upper()

                                       i+=1

                                       firstLetterReached = False

                                       newWord = False

                                       break

                               i += 1

               else:           # Condition when first letter of word is yet to be found

                       while i < length:

                               if characters[i].isalpha():  

                                       firstLetterReached = True

                                       i += 1

                                       break

                               i += 1

       else:   # Condition when newWord is False

               while i < length:

                       # Search for a space

                       if characters[i] == ' ':

                               newWord = True

                               i += 1

                               break

                       i += 1

# Join all the characters with empty string '' in between them

newsentence = ''.join(characters)

# Print out the new sentence

print(newsentence)

The last two screenshots of the four are of this second program.

Verified answer

Concepts involved :

Basic application of string manipulation

1.string slicing

2.string traversing

3.string addition :adding two strings

4.string capitalize function: capitalizes the chosen word or string

5.split function : to break a sentence into individual words that are stored in a list.

6.string indexing

(I also tried to keep in mind space complexity and time complexity of the program)

#Program to capitalize 2nd letter of each word

str=input('enter the string:')

a=str.split()

l=len(a)

c=''

for i in range(0,l):

   if len(a[i])>1:

       #string indexing

       b=a[i][0:1]+a[i][1].capitalize()+a[i][2:]

       c=c+b+' '

   else:

       c=c+a[i]+' '

print(c)

Hope this helps