Data commit

Task/CUSIP/Scala/cusip.scala

@@ -0,0 +1,28 @@
+object Cusip extends App {
+
+  val candidates = Seq("037833100", "17275R102", "38259P508", "594918104", "68389X106", "68389X105")
+
+  for (candidate <- candidates)
+    printf(f"$candidate%s -> ${if (isCusip(candidate)) "correct" else "incorrect"}%s%n")
+
+  private def isCusip(s: String): Boolean = {
+    if (s.length != 9) false
+    else {
+      var sum = 0
+      for (i <- 0 until 7) {
+        val c = s(i)
+        var v = 0
+        if (c >= '0' && c <= '9') v = c - 48
+        else if (c >= 'A' && c <= 'Z') v = c - 55 // lower case letters apparently invalid
+        else if (c == '*') v = 36
+        else if (c == '@') v = 37
+        else if (c == '#') v = 38
+        else return false
+        if (i % 2 == 1) v *= 2 // check if odd as using 0-based indexing
+        sum += v / 10 + v % 10
+      }
+      s(8) - 48 == (10 - (sum % 10)) % 10
+    }
+  }
+
+}