CalculatorViewModel.kt

class CalculatorViewModel : ViewModel() {
    var v1 by mutableStateOf("0")
    var v2 by mutableStateOf("0")
    val result = snapshotFlow { v1 to v2 }.mapLatest {
        sum(it.first, it.second)
    }.stateIn(viewModelScope, SharingStarted.Lazily, "0")
}