From 537036f41b5074b070f99619e664afbed58bd55b Mon Sep 17 00:00:00 2001
From: Dan Buch <daniel.buch@gmail.com>
Date: Mon, 14 May 2012 00:32:10 -0400
Subject: [PATCH] First quicksort version

although the tutorial did not have a class or object definition,
which is necessary according to sbt ...   hmmm.
---
 scala/official-by-example/.env                |  2 ++
 scala/official-by-example/.gitignore          |  2 ++
 scala/official-by-example/byx/build.sbt       |  3 +++
 .../byx/src/main/scala/sort.scala             | 23 +++++++++++++++++++
 scala/official-by-example/setup               | 10 ++++++++
 5 files changed, 40 insertions(+)
 create mode 100644 scala/official-by-example/.env
 create mode 100644 scala/official-by-example/.gitignore
 create mode 100644 scala/official-by-example/byx/build.sbt
 create mode 100644 scala/official-by-example/byx/src/main/scala/sort.scala
 create mode 100755 scala/official-by-example/setup

diff --git a/scala/official-by-example/.env b/scala/official-by-example/.env
new file mode 100644
index 0000000..580223b
--- /dev/null
+++ b/scala/official-by-example/.env
@@ -0,0 +1,2 @@
+HERE=$(dirname "$1")
+(echo "$PATH" | grep "$HERE/bin" >/dev/null 2>&1) || export PATH="$HERE/bin:$PATH"
diff --git a/scala/official-by-example/.gitignore b/scala/official-by-example/.gitignore
new file mode 100644
index 0000000..f984205
--- /dev/null
+++ b/scala/official-by-example/.gitignore
@@ -0,0 +1,2 @@
+/bin/
+target/
diff --git a/scala/official-by-example/byx/build.sbt b/scala/official-by-example/byx/build.sbt
new file mode 100644
index 0000000..d92a28b
--- /dev/null
+++ b/scala/official-by-example/byx/build.sbt
@@ -0,0 +1,3 @@
+name := "byx"
+
+version := "0.1.0"
diff --git a/scala/official-by-example/byx/src/main/scala/sort.scala b/scala/official-by-example/byx/src/main/scala/sort.scala
new file mode 100644
index 0000000..2ce98cc
--- /dev/null
+++ b/scala/official-by-example/byx/src/main/scala/sort.scala
@@ -0,0 +1,23 @@
+object sort {
+  def sort(xs: Array[Int]) {
+    def swap(i: Int, j: Int) {
+      val t = xs(i); xs(i) = xs(j); xs(j) = t
+    }
+    def sort1(l: Int, r: Int) {
+      val pivot = xs((l + r) / 2)
+      var i = l; var j = r
+      while (i <= j) {
+        while (xs(i) < pivot) i += 1
+        while (xs(j) > pivot) j -= 1
+        if (i <= j) {
+          swap(i, j)
+          i += 1
+          j -= 1
+        }
+      }
+      if (l < j) sort1(l, j)
+      if (j < r) sort1(i, r)
+    }
+    sort1(0, xs.length - 1)
+  }
+}
diff --git a/scala/official-by-example/setup b/scala/official-by-example/setup
new file mode 100755
index 0000000..4032ce5
--- /dev/null
+++ b/scala/official-by-example/setup
@@ -0,0 +1,10 @@
+#!/bin/bash
+
+set -e
+
+mkdir -p ./bin
+pushd ./bin
+curl -O 'https://raw.github.com/paulp/sbt-extras/master/sbt'
+chmod +x sbt
+popd
+./bin/sbt -sbt-create about