Write the countVowels function which counts the number of vowels using the string class as follows: int countVowels(const string& s) Write a test program that prompts the user to enter a string,...

Write the countVowels function which counts the number of vowels using the string class as follows:

int countVowels(const string& s)

Write a test program that prompts the user to enter a string, invokes the countVowels function and displays the total number of vowels in the string.