Add a character before two consecutive vowels in a sentence? Python-CodePudding

I'm trying to add the letter 'X' before each vowel in a string or sentence, however, when there is a repeated vowel, the letter 'X' should only be written once. For example, the word 'speeding' should look like this 'spXeedXing' but i'm getting 'spXeXedXing'.

I know why I'm getting this problem but don't know where to go from here to make it work.

Code below

def vowels(string):
    newString = ""
    for letter in string:
        if letter in "aeiou":
            newString  = "X"   letter
        else:
            newString  = letter

    print(newString)         
                
            
            
if __name__ == "__main__":
    vowels("speeding")

CodePudding user response：

>>> import re
>>> re.sub('([aeiou] )','X\g<1>','speeding')
'spXeedXing'
>>>

CodePudding user response：

You should create a new variable to track the previous letter in string. Check if the letters are continuous and only add X if the previous char is not the same as the current char.

def vowels(string):
    newString = ""
    i = 0 # Create a counter variable
    for letter in string:
        if (letter in "aeiou" and letter != string[i-1]) or (letter in "aeiou" and i == 0 and letter == string[i-1]): # Change this condition.  
            i  = 1 
            newString  = "X"   letter

        else:
            newString  = letter
            i  = 1 # Increment counter variable

    print(newString)

if __name__ == "__main__":
    vowels("speeding")

Output:

spXeedXing

Other test cases:

vowels("oompaloompas")
XoompXalXoompXas

vowels("eerie")
XeerXiXe

CodePudding user response：

You can let a regex do all the state-machine hard work...

To prepend 'X' to any number of consecutive vowels:

import re

s = 'speeding'
>>> re.sub(r'([aeiou] )', r'X\1', s)
'spXeedXing'

To prepend 'X' only to the same repeating vowel:

s = 'speeding'
>>> re.sub(r'(([aeiou])\2*)', r'X\1', s)
'spXeedXing'

s = 'toaster'
>>> re.sub(r'(([aeiou])\2*)', r'X\1', s)
'tXoXastXer'

CodePudding user response：

Here is a simple non-regex version:

def vowels(word):
    new_word = ""
    prev = ""  # no previous letter at first
    for letter in word:
        if letter in "aeiou" and letter != prev: 
            new_word  = "X"   letter
        else:
            new_word  = letter
        prev = letter  # keep to avoid insertion for repeats

    return new_word

if __name__ == "__main__":
    print(vowels("speeding"))
    print(vowels("eerie"))
    print(vowels("aaaaaaaaaaaaaargh"))

producing

spXeedXing
XeerXiXe
Xaaaaaaaaaaaaaargh

CodePudding user response：

you should try checking the previous letter in the string to see if it is the same letter as the current index

def vowels(string):
    newString = ""
    for i in range(len(string)):
        if string[i] in "aeiou":
            if string[i - 1] == string[i]:
                newString  = string[i]
            else:
                newString  = "X"   string[i]
        else:
            newString  = string[i]

print(newString)