What's the optimal data structure to store a String grid in Kotlin?

Question

What's an optimal data structure to store a String grid like this one and how to concisely convert the String into that data type?

"""10 15 20 11 14 19 04 10 18 63 92 68"""

I want to have easy access to any number from the grid by using a pair of coordinates.

Answer 1

You could use list of lists like this:

val grid: List<List<String>> = listOf(
    listOf("10", "15", "20"),
    listOf("14", "19", "04"),
    listOf("18", "63", "92")
)

val elem = grid[1][1]

You also could write your own extension function and use it with pairs:

fun List<List<String>>.get(i: Pair<Int, Int>) = this[i.first][i.second]
val element = grid.get(1 to 1)

Update

You could create list of lists from string with this helper extension function:

fun String.asGrid(size: Int): List<List<String>> = split(" ", "\n").chunked(size)

In this case at first we split our string to separate numbers and get collection of strings List<String>. And after this we chunk this list to get List<List<String>>

Usage:

val grid = """10 15 20 11
              14 19 04 10
              18 63 92 68""".asGrid(4)