Scala : add recfun

2 files changed, 68 insertions, 0 deletions

diff --git a/Scala/recfun/src/main/scala/common/package.scala b/Scala/recfun/src/main/scala/common/package.scala
new file mode 100644
index 0000000..f1c74c3
--- /dev/null
+++ b/Scala/recfun/src/main/scala/common/package.scala
@@ -0,0 +1,40 @@
+import java.io.File
+
+package object common {
+
+  /** An alias for the `Nothing` type.
+   *  Denotes that the type should be filled in.
+   */
+  type ??? = Nothing
+
+  /** An alias for the `Any` type.
+   *  Denotes that the type should be filled in.
+   */
+  type *** = Any
+
+  
+  /**
+   * Get a child of a file. For example,
+   * 
+   *   subFile(homeDir, "b", "c")
+   * 
+   * corresponds to ~/b/c
+   */
+  def subFile(file: File, children: String*) = {
+    children.foldLeft(file)((file, child) => new File(file, child))
+  }
+
+  /**
+   * Get a resource from the `src/main/resources` directory. Eclipse does not copy
+   * resources to the output directory, then the class loader cannot find them.
+   */
+  def resourceAsStreamFromSrc(resourcePath: List[String]): Option[java.io.InputStream] = {
+    val classesDir = new File(getClass.getResource(".").toURI)
+    val projectDir = classesDir.getParentFile.getParentFile.getParentFile.getParentFile
+    val resourceFile = subFile(projectDir, ("src" :: "main" :: "resources" :: resourcePath): _*)
+    if (resourceFile.exists)
+      Some(new java.io.FileInputStream(resourceFile))
+    else
+      None
+  }
+}
diff --git a/Scala/recfun/src/main/scala/recfun/Main.scala b/Scala/recfun/src/main/scala/recfun/Main.scala
new file mode 100644
index 0000000..277aa1a
--- /dev/null
+++ b/Scala/recfun/src/main/scala/recfun/Main.scala
@@ -0,0 +1,28 @@
+package recfun
+import common._
+
+object Main {
+  def main(args: Array[String]) {
+    println("Pascal's Triangle")
+    for (row <- 0 to 10) {
+      for (col <- 0 to row)
+        print(pascal(col, row) + " ")
+      println()
+    }
+  }
+
+  /**
+   * Exercise 1
+   */
+  def pascal(c: Int, r: Int): Int = ???
+
+  /**
+   * Exercise 2
+   */
+  def balance(chars: List[Char]): Boolean = ???
+
+  /**
+   * Exercise 3
+   */
+  def countChange(money: Int, coins: List[Int]): Int = ???
+}