// Sudoku solution must satisfy all of the following rules:
// Each of the digits 1-9 must occur once in each row.
// Each of the digits 1-9 must occur once in each column.
// Each of the digits 1-9 must occur once in each 3x3 grid.
fun isValidSudoku3x3Grid(grid: Array<Array<Int>>): Boolean {
if (grid.size != 3 || grid[0].size != 3) {
return false // Ensure it's a 3x3 grid
}
val seen = mutableSetOf<Int>()
for (row in grid) {
for (num in row) {
if (num < 1 || num > 9 || seen.contains(num)) {
return false // Invalid if number is out of range or repeated
}
seen.add(num)
}
}
return true // Valid if all numbers 1-9 appear exactly once
}
fun main() {
val grid = arrayOf(
arrayOf(5, 3, 4),
arrayOf(6, 7, 2),
arrayOf(1, 9, 8)
)
if (isValidSudoku3x3Grid(grid)) {
println("The grid is a valid Sudoku grid!")
} else {
println("The grid is NOT a valid Sudoku grid!")
}
}
/*
run:
The grid is a valid Sudoku grid!
*/
