Checking Whether Two Words Are Anagrams

In this lesson you will learn how to check whether two words are anagrams in Kotlin, covering how to sort and compare strings. This is for anyone searching for "Kotlin anagram check implementation".

An anagram is a different word made from the same letters rearranged (for example, listen and silent). Sort the letters of both strings and see whether they match.

The sample code lower-cases each string and sorts it as a list of characters with a.lowercase().toList().sorted(), doing the same to the other before comparing. "listen" and "silent" are made of the same letters, so they match once sorted.

A common stumbling block for beginners is not allowing for case differences. The sample folds to lower case with lowercase() before comparing; skip that and the same word in different cases is judged to be different.

It is a basic technique for comparing strings while ignoring order, and for long strings, counting how often each character occurs is faster.

📖 Reference code

fun isAnagram(a: String, b: String): Boolean {
    return a.lowercase().toList().sorted() == b.lowercase().toList().sorted()
}

fun main() {
    println(isAnagram("listen", "silent"))
    println(isAnagram("hello", "world"))
}

✍️ Your code

Type your code, then press "Run"

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