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How to remove duplicate characters from a string in Kotlin

How to remove duplicate characters from a string in Kotlin.

Here's a step-by-step tutorial on how to remove duplicate characters from a string in Kotlin:

Step 1: Create a function to remove duplicate characters​

To start, let's create a function called removeDuplicates that takes a string as input and returns a new string with duplicate characters removed.

fun removeDuplicates(str: String): String {
    // logic to remove duplicate characters
}

Step 2: Convert the string to a character array​

Inside the removeDuplicates function, the first thing we need to do is convert the input string to a character array. This will allow us to iterate over each character of the string.

fun removeDuplicates(str: String): String {
    val charArray = str.toCharArray()
    // logic to remove duplicate characters
}

Step 3: Create a new string to store unique characters​

Next, let's create an empty string called result to store the unique characters from the input string.

fun removeDuplicates(str: String): String {
    val charArray = str.toCharArray()
    var result = ""
    // logic to remove duplicate characters
}

Step 4: Iterate over each character of the input string​

Now, we need to iterate over each character of the charArray and check if it is already present in the result string. If not, we append it to the result string.

fun removeDuplicates(str: String): String {
    val charArray = str.toCharArray()
    var result = ""
    
    for (char in charArray) {
        if (char !in result) {
            result += char
        }
    }
    
    return result
}

Step 5: Test the function​

Finally, let's test our removeDuplicates function with a sample string to see if it removes duplicate characters correctly.

fun main() {
    val str = "Hello World"
    val result = removeDuplicates(str)
    println(result) // Output: Helo Wrd
}

That's it! You have successfully removed duplicate characters from a string in Kotlin. You can use this removeDuplicates function in your Kotlin projects whenever you need to eliminate duplicate characters from a string.