- Added Scala solutions to week 89 by Laurent Rosenfeld.

2 files changed, 59 insertions, 0 deletions

diff --git a/challenge-089/laurent-rosenfeld/scala/ch-1.scala b/challenge-089/laurent-rosenfeld/scala/ch-1.scala
new file mode 100644
index 0000000000..500af82aac
--- /dev/null
+++ b/challenge-089/laurent-rosenfeld/scala/ch-1.scala
@@ -0,0 +1,21 @@
+object Main {
+  def main(args: Array[String]): Unit = {
+    val in: Int = if (args.size == 1) args(0).toInt else 10
+    var sum = 0
+    for (m <- 1 to in) {
+      for (n <- m + 1 to in) {
+        sum += gcd(m, n)
+      }
+    }
+    println(s"Sum of GCD to $in is $sum")
+  }
+  def gcd(a: Int, b: Int): Int = {
+    var (i, j) = (a, b)
+    while (j > 0) {
+      var t = i
+      i = j
+      j = t % j
+    }
+    return i
+  }
+}
diff --git a/challenge-089/laurent-rosenfeld/scala/ch-2.scala b/challenge-089/laurent-rosenfeld/scala/ch-2.scala
new file mode 100644
index 0000000000..a410591dba
--- /dev/null
+++ b/challenge-089/laurent-rosenfeld/scala/ch-2.scala
@@ -0,0 +1,38 @@
+import Array._
+object Main {
+  def main(args: Array[String]): Unit = {
+    var mat = range(1, 10)
+    var in = Array.empty[Int]
+    permute(in, mat)
+  }
+  def print_matrix(a: Array[Int]): Unit = {
+    println(s"[ ${a(0)} ${a(1)} ${a(2)} ]")
+    println(s"[ ${a(3)} ${a(4)} ${a(5)} ]")
+    println(s"[ ${a(6)} ${a(7)} ${a(8)} ]")
+    println(" ")
+  }
+  def permute(in: Array[Int], left: Array[Int]): Unit = {
+    val sum = 15
+    if (left.size == 0) {
+      if (
+        in.slice(0, 3).sum != sum ||
+        in.slice(3, 6).sum != sum ||
+        in.slice(6, 9).sum != sum ||
+        in(0) + in(3) + in(6) != sum ||
+        in(1) + in(4) + in(7) != sum ||
+        in(2) + in(5) + in(8) != sum ||
+        in(0) + in(4) + in(8) != sum ||
+        in(2) + in(4) + in(6) != sum
+      ) {
+        return
+      }
+      print_matrix(in)
+      return
+    }
+    for (candidate <- left) {
+      val values: Array[Int] = in.appended(candidate)
+      val newleft: Array[Int] = left.filter(_ != candidate)
+      permute(values, newleft)
+    }
+  }
+}