From 95c661a12b81513cdddc3977c02262668a58a68c Mon Sep 17 00:00:00 2001
From: simon-dueck <126712673+simon-dueck@users.noreply.github.com>
Date: Tue, 28 Mar 2023 14:11:38 -0500
Subject: Added solution for challenge 2

---
 challenge-210/simon-dueck/fsharp/ch-2.fsx | 48 +++++++++++++++++++++++++++++++
 1 file changed, 48 insertions(+)
 create mode 100644 challenge-210/simon-dueck/fsharp/ch-2.fsx

diff --git a/challenge-210/simon-dueck/fsharp/ch-2.fsx b/challenge-210/simon-dueck/fsharp/ch-2.fsx
new file mode 100644
index 0000000000..1dde08cc63
--- /dev/null
+++ b/challenge-210/simon-dueck/fsharp/ch-2.fsx
@@ -0,0 +1,48 @@
+(*
+    You are given an array of integers which can move in right
+    direction if it is positive and left direction when negative.
+
+    If two numbers collide then the smaller one will explode.
+    And if both are same then they both explode.
+    We take the absolute value in consideration when comparing.
+    
+    All numbers move at the same speed, therefore any 2 numbers
+    moving in the same direction will never collide.
+    
+    Write a script to find out who survives the collision.
+*)
+
+let abs a = if a > 0 then a else 0 - a
+
+let collide a b: int option =
+    if (abs a) = (abs b) then None
+    elif (abs a) > (abs b) then Some(a)
+    else Some(b)
+
+let number_collision arr: int list =
+
+    let rec advance = function
+        | x::y::xs when x > 0 && y < 0 -> 
+            match collide x y with
+            | Some(w) when w > 0 -> advance (w :: xs)
+            | Some(w) -> w :: (advance xs)
+            | None -> advance xs
+        | x::y::xs when x > 0 && y > 0 || x < 0 && y < 0 ->
+            x :: advance (y::xs)
+        | x -> x
+
+    let rec repeat arr =
+        let advanced = advance arr
+        if advanced = arr then advanced
+        else repeat advanced
+
+    repeat arr
+
+let a = [2; 3; -1;]
+printfn $"{number_collision a}"
+
+let b = [3; 2; -4;]
+printfn $"{number_collision b}"
+
+let c = [1; -1;]
+printfn $"{number_collision c}"
\ No newline at end of file
-- 
cgit