Question

Many documents use a specific format for a person's name. Write a program whose input is:

firstName middleName lastName

and whose output is:

lastName, firstInitial.middleInitial.

If the input has the form:

firstName lastName

the output is:

lastName, firstInitial.

Ex: If the input is:

user_input = input()
splits = user_input.split(" ")
if(len(splits) == 3):
first_name = splits[0]
middle_name = splits[1]
last_name = splits[2]
print(last_name + ", " + first_name[0] + "." + middle_name[0] + ".")
elif(len(splits) == 2):
first_name = splits[0]
middle_name = splits[1]
print(middle_name + ", " + first_name[0] + ".")
  

I got helped on this, but someone explain to me line by line what it means? Splits == 3, how do I know it's three?! the [0] and [1] why does first name have[0] what does the 0, 1 mean?!!

Answer 1

Program: In this program, we are taking input from the user, and then after the processing the string we output the string in specific format.

Steps:

• First we split the string based on the spaces as regex using the split function and store it in a list called splits
• The size of our list depends on the input given by the user, if the user input included first name, middle name and last name, then our size of list would be three - ["firstName","middleName","lastName"], which is checked by the if condition - if(len(splits) == 3), here "len" is an inbuilt function which returns size of array/list. If the user input included only first name and last name, the size of list would be two - ["firstName","lastName"].
• Then we store the firstname, middleName (if present), lastName in different variables. As we want to print the full last name, but only initials of firstName and middleName, so to print the first character of the string first_name we have to print the character present at index 0 index which would be written as first_name[0] and similarly for middle name middle_name[0].
• Print the result

We can access any character of a string using its indices, for e.g - fruit = "apple", if we print fruit[0] we get 'a' as output, if we print fruit[1] we get 'p' as output and similarly if we print fruit[4] we get 'e' as output.

Below is the code with comments for more visualisation:

Code:

user_input = input()

# The slit() function splits the string input based on the regex passed in it
# and returns a list of strings, here we are storing it in a variable named splits
# Here we passed space as our regex and hence our input would be split based on the spaces in the string input
# for e.g - input => Mary Elizabeth Smith
# splits = ["Mary", "Elizabeth", "Smith"]
splits = user_input.split(" ")

# If user input was - firstName middleName lastName
# splits would have a list of size 3 like this ["firstName","middleName","LastName"]
# at index 0 we have first name, at index 1 middle name, and at index 2 last name
if(len(splits) == 3):
    
    # Store firstName, first element of splits list
    first_name = splits[0]
    
    # Store middleName, second element of splits list
    middle_name = splits[1]
    
    # Store lastName, third element of splits list
    last_name = splits[2]
    
    # As we want to access the first characters of first name and middle name
    # the first character is stored at 0th index, first_name[0] would give first character of first name
    # and middle_name[0] would give first character of middle name
    
    # Print lastName, firstInitial.middleInitial.
    print(last_name + ", " + first_name[0] + "." + middle_name[0] + ".")
    
# else if the input was - firstName lastName
# splits would have a list of size 2 like this ["firstName","lastName"]
# at index 0 we have first name, at index 1 last name
elif(len(splits) == 2):
    
    #Store firstName, first element of splits list
    first_name = splits[0]
    
    #Store lastName, second element of splits list
    middle_name = splits[1]
    
    # As we want to access the first character of first name and middle name
    # the first character is stored at 0th index, first_name[0] would give first character of first name
    
    #Print lastName, firstInitial.
    print(middle_name + ", " + first_name[0] + ".")
  

Code image:

Output 1:

Output 2:

# Please ask for any doubts. Thanks.