inline fun CharSequence.reduceRightIndexed(
    operation: (index: Int, Char, acc: Char) -> Char
): Char

Accumulates value starting with last character and applying operation from right to left to each character with its index in the original char sequence and current accumulator value.


operation - function that takes the index of a character, the character itself and current accumulator value, and calculates the next accumulator value.