Во введенном тексте найти слово, в котором доля гласных максимальна

#include <iostream>
#include <cstddef>
#include <string>
#include <vector>
#include <sstream>
 
bool is_vowel(char ch)
{
    return ch == 'a' || ch == 'o' || ch == 'i' || ch == 'e' || ch == 'u' || ch == 'y';
}
 
std::size_t count_vowels(const std::string & word)
{
    std::size_t numberOfVowels = 0;
    for (const auto elem : word)
        if (is_vowel(elem))
            ++numberOfVowels;
    return numberOfVowels;
}
 
std::vector<std::string> split(const std::string& text, char delimiter)
{   // Thanks to Jonathan Boccara for this function
    std::vector<std::string> tokens;
    std::string token;
    std::istringstream tokenStream(text);
    while (std::getline(tokenStream, token, delimiter))
        tokens.push_back(token);
    return tokens;
}
 
std::string max_vowels_word(const std::vector<std::string> & words)
{
    std::string maxVowelsWord = words.at(0);
    for (const auto & elem : words)
        if (count_vowels(elem) > count_vowels(maxVowelsWord))
            maxVowelsWord = elem;
    return maxVowelsWord;
}
 
int main()
{
    std::cout << "Enter your text:\n";
    std::string text;
    std::getline(std::cin, text);
    std::vector<std::string> words(split(text, ' '));
    std::cout << "The first word contains biggest number of vowels: " << max_vowels_word(words);
}

#include <iostream>
#include <cstddef>
#include <string>
#include <vector>
#include <sstream>
 
bool is_vowel(char ch)
{
    return ch == 'a' || ch == 'o' || ch == 'i' || ch == 'e' || ch == 'u' || ch == 'y';
}
 
std::size_t count_vowels(const std::string & word)
{
    std::size_t numberOfVowels = 0;
    for (std::string::const_iterator it = word.cbegin(); it != word.cend(); ++it)
        if (is_vowel(*it))
            ++numberOfVowels;
    return numberOfVowels;
}
 
std::vector<std::string> split(const std::string & text, char delimiter)
{   // Thanks to Jonathan Boccara for this function
    std::vector<std::string> tokens;
    std::string token;
    std::istringstream tokenStream(text);
    while (std::getline(tokenStream, token, delimiter))
        tokens.push_back(token);
    return tokens;
}
 
std::string max_vowels_word(const std::vector<std::string> & words)
{
    std::string maxVowelsWord = words.at(0);
    for (std::vector<std::string>::const_iterator it = words.cbegin(); it != words.cend(); ++it)
        if (count_vowels(*it) > count_vowels(maxVowelsWord))
            maxVowelsWord = *it;
    return maxVowelsWord;
}
 
int main()
{
    std::cout << "Enter your text:\n";
    std::string text;
    std::getline(std::cin, text);
    std::vector<std::string> words(split(text, ' '));
    std::cout << "The first word contains biggest number of vowels: " << max_vowels_word(words);
}