Kotlin Map: Transform Both Key and Value

val data = mapOf(    1 to "Desmond",    2 to "Mei Ru")val newData = data.entries.associate { (key, value) ->    key to value}// or - performance of associate and associateBy should be equalval newData = data.entries.associateBy({(key, value) ->    value}, {(key, value) ->    key})// or - less efficientval newData = data.map { (key, value) ->    value to key}.toMap()

val newData = data.mapKeys { (key, value) ->    key - 1}

val newData = data.mapValues { (key, value) ->    value.toUpperCase()}