Fold and Reduce operations example in scala

Author: CodeLab20

Special_Functions/FoldAndReduce.scala

@@ -0,0 +1,39 @@
+/**
+ * foldLeft and foldRight will perform a reduction operation with a seed value.
+ * reduceLeft and reduceRight will perform a reduction operation without a seed value. 
+ * Fold and Reduce operations can be applied to List, Set, String, Map, Stream and Options.
+ **/
+object FoldAndReduce extends App
+{
+    //using foldLeft
+    val foldLeftRes = (1 to 10).foldLeft(0){(total:Int, next:Int) => 
+                                              println(s"Total: $total, Next:$next")
+                                              total + next}
+    println("foldLeftRes: " + foldLeftRes + "\n\n")
+    
+    //using reduceLeft
+    val reduceLeftRes = (1 to 10).reduceLeft{(total:Int, next:Int) => 
+                                              println(s"Total: $total, Next:$next")
+                                              total + next}
+    println("reduceLeftRes: " + reduceLeftRes + "\n\n")
+    
+    //using foldRight
+    val foldRightRes = (1 to 10).foldRight(0){(next:Int, total:Int ) => 
+                                              println(s"Total: $total, Next:$next")
+                                              total + next}
+    println("foldRightRes: " + foldRightRes + "\n\n")
+    
+    //using reduceRight
+    val reduceRightRes = (1 to 10).reduceRight{(next:Int, total:Int ) => 
+                                              println(s"Total: $total, Next:$next")
+                                              total + next}
+    println("reduceRightRes: " + reduceRightRes + "\n\n")
+
+    //alternatives for above functionalities
+    println("(1 to 10).sum : " + (1 to 10).sum)
+    println("(1 to 10).product : " + (1 to 10).product)
+    
+    //shorthand notation for foldLeft example
+    println("(1 to 10).foldLeft(0)(_ + _) : " + (1 to 10).foldLeft(0)(_ + _))
+    println("(1 to 10).mkString(\",\") : " + (1 to 10).mkString(","))
+}