fun main() {
val arr = arrayOf(floatArrayOf(6f, 1f, 1f), floatArrayOf(4f, -2f, 5f), floatArrayOf(2f, 8f, 7f))
val determinant = arr[0][0] * (arr[1][1] * arr[2][2] - arr[1][2] * arr[2][1]) -
arr[0][1] * (arr[1][0] * arr[2][2] - arr[1][2] * arr[2][0]) +
arr[0][2] * (arr[1][0] * arr[2][1] - arr[1][1] * arr[2][0])
println(determinant)
}
/*
a b c
arr = d e f
g h i
determinant = a*(e*i - f*h) - b*(d*i-f*g) + c*(d*h - e*g)
*/
/*
run:
-306.0
*/