Arrays and two-dimensional traversal

The idea

IntArray stores primitive integer elements, while Array<Int> is a generic array representation. Both use zero-based positions and allow element replacement. A two-dimensional structure is usually an array of row arrays, so rows may have different lengths. Use each row’s own indices when ragged data is supported; assuming the first row’s width can skip values or access missing positions.

For rectangular problems, state the nonempty and equal-width preconditions before using column-oriented loops. A maximum-selection algorithm also needs a tie policy. Initializing from a valid candidate handles negative totals, and updating only when a new total is strictly greater preserves the earliest winner. Keep input mutation separate from analysis so a report function cannot accidentally alter the data it is summarizing.

fun main(){ val grid=arrayOf(intArrayOf(2,4),intArrayOf(7),intArrayOf(1,3,5)); var total=0; for(row in grid) for(value in row) total+=value; println(total) }

22

Nested value traversal naturally visits every element even though the rows have different lengths.