We are required to write a JavaScript function that takes in a string that might contain some alphabets. The function should count and return the number of vowels that exists in the string.
Example
Following is the code −
const str = 'this is a string'; const countVowels = (str = '') => { str = str.toLowerCase(); const legend = 'aeiou'; let count = 0; for(let i = 0; i < str.length; i++){ const el = str[i]; if(!legend.includes(el)){ continue; }; count++; }; return count; }; console.log(countVowels(str));
Output
Following is the output on console −
4