Create BinarySearch in Scala

Author: kelvins

README.md

@@ -228,8 +228,8 @@ In order to achieve greater coverage and encourage more people to contribute to
                 </a>
             </td>
             <td> <!-- Scala -->
-                <a href="./CONTRIBUTING.md">
-                    <img align="center" height="25" src="./logos/github.svg" />
+                <a href="./src/scala/BinarySearch.scala">
+                    <img align="center" height="25" src="./logos/scala.svg" />
                 </a>
             </td>
             <td> <!-- Kotlin -->

src/scala/BinarySearch.scala

@@ -0,0 +1,23 @@
+import scala.annotation.tailrec
+
+def binarySearch(data: Seq[Int], target: Int): Option[Int] = {
+  @tailrec
+  def search(left: Int, right: Int): Option[Int] = {
+    if (left > right) None
+    else {
+      val middle: Int = (left + right) / 2
+      if (data(middle) == target) Some(middle)
+      else if (data(middle) < target) search(middle + 1, right)
+      else search(left, middle - 1)
+    }
+  }
+  search(0, data.size)
+}
+
+object Main extends App {
+  val data: Seq[Int] = Seq(0, 1, 3, 5, 6, 7, 8, 9, 10, 11, 12)
+  val value: Int = 11
+  println(
+    s"Value '$value' found in position '${binarySearch(data, value).get}'"
+  )
+}