From c8a4ea77712e5a42ca7f78338b4f6ebf4c227bd5 Mon Sep 17 00:00:00 2001
From: "R. Tyler Croy" <tyler@monkeypox.org>
Date: Sun, 13 Mar 2011 23:22:20 -0700
Subject: [PATCH] Add solution for problem eight

---
 eight.adb | 57 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 57 insertions(+)
 create mode 100644 eight.adb

diff --git a/eight.adb b/eight.adb
new file mode 100644
index 0000000..89b15fa
--- /dev/null
+++ b/eight.adb
@@ -0,0 +1,57 @@
+--
+--  Project Euler problem #8
+--
+--  Find the greatest product of five consecutive digits in the 1000-digit
+--  number.
+
+with Ada.Text_IO;
+
+use Ada.Text_IO;
+
+procedure Eight is
+    Source : constant String := "73167176531330624919225119674426574742355349194934" &
+                                "96983520312774506326239578318016984801869478851843" &
+                                "85861560789112949495459501737958331952853208805511" &
+                                "12540698747158523863050715693290963295227443043557" &
+                                "66896648950445244523161731856403098711121722383113" &
+                                "62229893423380308135336276614282806444486645238749" &
+                                "30358907296290491560440772390713810515859307960866" &
+                                "70172427121883998797908792274921901699720888093776" &
+                                "65727333001053367881220235421809751254540594752243" &
+                                "52584907711670556013604839586446706324415722155397" &
+                                "53697817977846174064955149290862569321978468622482" &
+                                "83972241375657056057490261407972968652414535100474" &
+                                "82166370484403199890008895243450658541227588666881" &
+                                "16427171479924442928230863465674813919123162824586" &
+                                "17866458359124566529476545682848912883142607690042" &
+                                "24219022671055626321111109370544217506941658960408" &
+                                "07198403850962455444362981230987879927244284909188" &
+                                "84580156166097919133875499200524063689912560717606" &
+                                "05886116467109405077541002256983155200055935729725" &
+                                "71636269561882670428252483600823257530420752963450";
+
+    function Digits_Product (Input : in String) return Natural is
+        Result : Natural := 1;
+    begin
+        for Item in Input'Range loop
+            Result := (Result * Natural'Value (Input (Item .. Item)));
+        end loop;
+
+        return Result;
+    end Digits_Product;
+
+    Highest : Natural := 0;
+begin
+    for Index in 1 .. (Source'Length - 5) loop
+        declare
+            Sub : constant String := Source (Index .. Index + 4);
+            Product : constant Natural := Digits_Product (Sub);
+        begin
+            if Product > Highest then
+                Highest := Product;
+            end if;
+        end;
+    end loop;
+
+    Put_Line ("> Highest product:" & Natural'Image (Highest));
+end Eight;