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exercises/intro/README.md

@@ -54,7 +54,7 @@ public class Loop {
 }
 ```
 
-Source: [Loop1.java]
+> Source: [Loop1.java]
 
 This program is, on purpose, easy enough to understand. Consider however, that 
 in your real programming work you might deal with several complexities at the same
@@ -105,7 +105,7 @@ object Main extends App {    // 1.
 }
 ```
 
-Source: [Loop2.scala]
+> Source: [Loop2.scala]
 
 First you notice that Scala is less verbose: no semicolons needed, no `public
  static void main`, no explicit reassignment of `x` in `for` loop. Here are 
@@ -200,7 +200,7 @@ def sum(xs: List[Int]): Int = {
 val result = sum(square(filterEven(iterate(10))))
 ```
 
-Source: [Loop3.scala]
+> Source: [Loop3.scala]
 
 Wow! The number of lines of code just exploded and we introduced a lot of 
 duplication along the way. Let's review the function body implementation:
@@ -342,7 +342,8 @@ def sum(xs: List[Int]): Int = {
 }
 ```
 
-Source: [Loop4.scala]
+> Source: [Loop4.scala]<br>
+> Diff: [Loop3.scala => Loop4.scala]
 
 Here we pattern match on a list instead of integer. Note how we used the same
 list construction syntax in the `case` expression to capture list's head `x` 
@@ -390,7 +391,8 @@ def square(xs: List[Int]): List[Int] =
   flatMap(xs, x => List(x * x))
 ```
 
-Source: [Loop5.scala]
+> Source: [Loop5.scala]<br>
+> Diff: [Loop4.scala => Loop5.scala]
 
 1. `flatMap` takes function `f` as its second argument;
 2. `A => B` is type annotation for a function that takes an argument of type 
@@ -441,7 +443,8 @@ def sum(xs: List[Int]): Int =
   foldLeft(xs)(0)((acc, x) => acc + x)
 ```
 
-Source: [Loop6.scala]
+> Source: [Loop6.scala]<br>
+> Diff: [Loop5.scala => Loop6.scala]
 
 1. `foldLeft[A, R]` is parametrized on type of the input list `A` as well as 
 the type of its return value `R` thus `foldLeft` is a *generic* function;
@@ -486,7 +489,8 @@ def sumOfEvenSquares(max: Int): Int = {
 }
 ```
 
-Source: [Loop7.scala]
+> Source: [Loop7.scala]<br>
+> Diff: [Loop6.scala => Loop7.scala]
 
 Here, `square` really does only what it says and doesn't mess with lists 
 anymore, which is now the responsibility of `map`.
@@ -511,7 +515,8 @@ def sumOfEvenSquares(max: Int): Int = {
 }
 ```
 
-Source: [Loop8.scala]
+> Source: [Loop8.scala]<br>
+> Diff: [Loop7.scala => Loop8.scala]
 
 We use `1 to 10` directly instead of our own `iterate` function. `filter`, 
 `map`, `sum` as well as `flatMap`, `foldLeft` and many more functions are 
@@ -532,8 +537,13 @@ transformations without changing the existing ones.
 [Loop1.scala]: https://github.com/SingaporeScalaProgrammers/scala-workshop/blob/master/references/intro/src/main/scala/Loop1.scala
 [Loop2.scala]: https://github.com/SingaporeScalaProgrammers/scala-workshop/blob/master/references/intro/src/main/scala/Loop2.scala
 [Loop3.scala]: https://github.com/SingaporeScalaProgrammers/scala-workshop/blob/master/references/intro/src/main/scala/Loop3.scala
+[Loop3.scala => Loop4.scala]: https://rawgit.com/SingaporeScalaProgrammers/scala-workshop/master/references/intro/diff/Loop3-Loop4.html
 [Loop4.scala]: https://github.com/SingaporeScalaProgrammers/scala-workshop/blob/master/references/intro/src/main/scala/Loop4.scala
+[Loop4.scala => Loop5.scala]: https://rawgit.com/SingaporeScalaProgrammers/scala-workshop/master/references/intro/diff/Loop4-Loop5.html
 [Loop5.scala]: https://github.com/SingaporeScalaProgrammers/scala-workshop/blob/master/references/intro/src/main/scala/Loop5.scala
+[Loop5.scala => Loop6.scala]: https://rawgit.com/SingaporeScalaProgrammers/scala-workshop/master/references/intro/diff/Loop5-Loop6.html
 [Loop6.scala]: https://github.com/SingaporeScalaProgrammers/scala-workshop/blob/master/references/intro/src/main/scala/Loop6.scala
+[Loop6.scala => Loop7.scala]: https://rawgit.com/SingaporeScalaProgrammers/scala-workshop/master/references/intro/diff/Loop6-Loop7.html
 [Loop7.scala]: https://github.com/SingaporeScalaProgrammers/scala-workshop/blob/master/references/intro/src/main/scala/Loop7.scala
+[Loop7.scala => Loop8.scala]: https://rawgit.com/SingaporeScalaProgrammers/scala-workshop/master/references/intro/diff/Loop7-Loop8.html
 [Loop8.scala]: https://github.com/SingaporeScalaProgrammers/scala-workshop/blob/master/references/intro/src/main/scala/Loop8.scala