Adding the comments for the early CS's

CS3 - Challenge Solution/Main.java

@@ -1,9 +1,18 @@
 import java.util.Scanner;
 
+/*
+    CS3 Challenge Solution
+
+    Original Challenge Description: Build a program that requests
+    three numbers from the user, and performs a math operation on 
+    them and prints the result. 
+*/
 public class Main {
     public static void main(String[] args) {
+        //Start with setting up System.in through a Scanner
         Scanner scan = new Scanner(System.in);
 
+        //Grab three values from the user, all of them are doubles
         System.out.print("Value 1: ");
         double firstValue = scan.nextDouble();
 
@@ -13,8 +22,17 @@ public class Main {
         System.out.print("Value 3: ");
         double thirdValue = scan.nextDouble();
 
+        //Print out the operation being performed. Two things of note here, 
+        //the first thing in the println is an empty string, this helps Java to know
+        //that it's supposed to be combining Strings, not attempting to do regular
+        //mathematical addition.
+        //The second thing is that we have the actual math at the end of the println
+        //statement wrapped in parenthesis. This helps to ensure that Java treats 
+        //that as a math operation, and separates it from all of the combining of Strings
+        //that is going on outside the parenthesis. 
         System.out.println("" + firstValue + " / " + secondValue + " - " + thirdValue + " = " + (firstValue / secondValue - thirdValue));
 
+        //Close the scanner, because good practice. 
         scan.close();
     }
 }