Given a name, print the initials of a name(uppercase) with last name(with first alphabet in uppercase) written in full separated by dots.
Examples:
Input : Lazyroar for Lazyroar Output : G.F.Geeks Input : mohandas karamchand gandhi Output : M.K.Gandhi
A naive approach of this will be to iterate for spaces and print the next letter after every space except the last space. At last space we have to take all the characters after the last space in a simple approach. Using Python in inbuilt functions we can split the words into a list, then traverse till the second last word and print the first character in capitals using upper() function in python and then add the last word using title() function in Python which automatically converts the first alphabet to capital.
Implementation:
Python3
# python program to print initials of a namedef name(s): # split the string into a list l = s.split() new = "" # traverse in the list for i in range(len(l)-1): s = l[i] # adds the capital first character new += (s[0].upper()+'.') # l[-1] gives last item of list l. We # use title to print first character in # capital. new += l[-1].title() return new # Driver code s ="mohandas karamchand gandhi"print(name(s)) |
M.K.Gandhi
The time complexity of this algorithm is O(n) where n is the number of words in the string. This is because the algorithm only iterates through the string once.
The space complexity of this algorithm is O(n) because a new string is created and all the words in the string are stored in a list.
Using regular expressions:
Algorithm:
- Import the re module for using regular expressions.
- Define a function name which takes a string as input.
- Use the re.findall() function to extract the first letter of each word in the string s. The regular expression ‘\b\w’ matches the first letter of each word. The ‘\b’ specifies a word boundary and ‘\w’ matches any alphanumeric character.
- Use the re.findall() function again to extract the last word in the string s. The regular expression ‘\b\w+$’ matches the last word in the string. The ‘$’ specifies the end of the string.
- Combine the initials and last name with dots using the join() function. The join() function concatenates the elements of a list into a string using a specified delimiter.
- Convert the initials to uppercase and last name to title case (i.e. capitalize the first letter of each word).
- Return the result.
Python3
import redef name(s): # Use regular expression to extract the first letter of each word initials = re.findall(r'\b\w', s) # Use regular expression to extract the last word last_name = s.split()[-1] # Combine the initials and last name with dots result = '.'.join(initials[:-1]).upper() + '.' + last_name.title() return result#Driver codes = "mohandas karamchand gandhi"print(name(s)) |
M.K.Gandhi
Time complexity: The time complexity of the regular expression approach is O(n), where n is the length of the input string s. This is because the re.findall() function iterates over the string s once to extract the required characters.
Space complexity: The space complexity of the regular expression approach is O(n), where n is the length of the input string s. This is because the re.findall() function creates a list to store the extracted characters, and the result string also takes up space proportional to the length of s.
