From 203143b97aa454248593ab64c097f6bd70a4e4ab Mon Sep 17 00:00:00 2001
From: Jakub Kramarz <jakub.kramarz@freshmail.pl>
Date: Sun, 1 Jan 2017 13:04:55 +0100
Subject: [PATCH] reimplemented unhash using Horner's method

---
 hashids-scala/src/main/scala/org/hashids/impl/package.scala | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/hashids-scala/src/main/scala/org/hashids/impl/package.scala b/hashids-scala/src/main/scala/org/hashids/impl/package.scala
index 82f660f..7b6a5c3 100644
--- a/hashids-scala/src/main/scala/org/hashids/impl/package.scala
+++ b/hashids-scala/src/main/scala/org/hashids/impl/package.scala
@@ -43,8 +43,8 @@ package object impl {
   }
 
   def unhash(input: String, alphabet: String): Long = {
-    input.zipWithIndex.foldLeft[Long](0L) { case (acc, (in, i)) =>
-      acc + (alphabet.indexOf(in) * Math.pow(alphabet.length, input.length - 1 - i)).toLong
+    input.foldLeft[Long](0L) {
+      (carry, item) => carry * alphabet.length + alphabet.indexOf(item)
     }
   }