Lua solutions for week 075

2 files changed, 92 insertions, 0 deletions

diff --git a/challenge-075/abigail/lua/ch-1.lua b/challenge-075/abigail/lua/ch-1.lua
new file mode 100644
index 0000000000..6d46469469
--- /dev/null
+++ b/challenge-075/abigail/lua/ch-1.lua
@@ -0,0 +1,43 @@
+#!/opt/local/bin/lua
+
+--
+-- See ../README.md
+--
+
+--
+-- Run as: lua ch-1.lua < input-file
+--
+
+function possibilities (target, coins, from, to)
+    if target == 0 then
+        return 1
+    end
+    if target < 0 or from > to then
+        return 0
+    end
+
+    local sum = 0
+
+    for i = 0, math . floor (target / coins [from]) do
+        sum = sum + possibilities (target - i * coins [from],
+                                                coins, from + 1, to)
+    end
+
+    return sum
+end
+
+
+for line in io . lines () do
+    local target
+    local coins = {}
+    local i
+    for i in line : gmatch ("%d+") do
+        if  target == nil then
+            target = tonumber (i)
+        else
+            table . insert (coins, tonumber (i))
+        end
+    end
+    print (possibilities (target, coins, 1, #coins))
+ 
+end
diff --git a/challenge-075/abigail/lua/ch-2.lua b/challenge-075/abigail/lua/ch-2.lua
new file mode 100644
index 0000000000..0765ff81b1
--- /dev/null
+++ b/challenge-075/abigail/lua/ch-2.lua
@@ -0,0 +1,49 @@
+#!/opt/local/bin/lua
+
+--
+-- See ../README.md
+--
+
+--
+-- Run as: lua ch-2.lua < input-file
+--
+
+for line in io . lines () do
+    local heights = {}
+    local h, i
+    local max_height = 0
+    for h in line : gmatch ("%d+") do
+        h = tonumber (h)
+        table . insert (heights, h)
+        if  max_height < h then
+            max_height = h
+        end
+    end
+
+    local max_area = 0
+    for h = 1, max_height do
+        local max = 0
+        local cur = 0
+        for i = 1, #heights do
+            if heights [i] >= h then
+                cur = cur + 1
+            else
+                if  max < cur then
+                    max = cur
+                end
+                cur = 0
+            end
+        end
+
+        if  max < cur then
+            max = cur
+        end
+
+        local area = max * h
+        if  max_area < area then
+            max_area = area
+        end
+    end
+
+    print (max_area)
+end