Kotlin function: Count vowels in a string

Last update on December 20 2024 12:55:36 (UTC/GMT +8 hours)

Write a Kotlin function `countVowels` that counts the number of vowels in a given string.

Sample Solution:

Kotlin Code:

fun countVowels(input: String): Int {
    val vowels = listOf('a', 'e', 'i', 'o', 'u')
    var count = 0

    for (char in input.lowercase()) {
        if (char in vowels) {
            count++
        }
    }

    return count
}

fun main() {
    val str = "Kotlin, function!"
    val vowelCount = countVowels(str)
    println("The number of vowels in '$str' is $vowelCount")
}

Sample Output:

The number of vowels in 'Kotlin, function!' is 5

Explanation:

In the above exercise -

• The "countVowels()" function takes a String parameter named input, representing the string in which the vowels need to be counted.
• A list of vowels is created, containing lowercase vowels ('a', 'e', 'i', 'o', 'u').
• A variable count is initialized to 0 to keep track of the vowel count.
• A for loop is used to iterate over each character in the input string (input. lowercase() is used to convert the string to lowercase for case-insensitive comparison).
• Inside the loop, each character is checked if it exists in the vowel list. If it does, the count is incremented.
• Finally, the count value is returned as the result of the function.
• In the "main()" function, a sample string str is defined.
• The "countVowels()" function is called with the string as an argument, and the result is stored in the "vowelCount" variable.
• The number of vowels in the string is then printed to the console using string interpolation.

Kotlin Editor:

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