Data commit

Task/McNuggets-problem/Lua/mcnuggets-problem.lua

@@ -0,0 +1,72 @@
+function range(A,B)
+    return function()
+        return coroutine.wrap(function()
+            for i = A, B do coroutine.yield(i) end
+        end)
+    end
+end
+
+function filter(stream, f)
+    return function()
+        return coroutine.wrap(function()
+            for i in stream() do
+                if f(i) then coroutine.yield(i) end
+            end
+        end)
+    end
+end
+
+function triple(s1, s2, s3)
+    return function()
+        return coroutine.wrap(function()
+            for x in s1() do
+                for y in s2() do
+                    for z in s3() do
+                        coroutine.yield{x,y,z}
+                    end
+                end
+            end
+        end)
+    end
+end
+
+function apply(f, stream)
+    return function()
+        return coroutine.wrap(function()
+            for T in stream() do
+                coroutine.yield(f(table.unpack(T)))
+            end
+        end)
+    end
+end
+
+function exclude(s1, s2)
+    local exlusions = {} for x in s1() do exlusions[x] = true end
+    return function()
+        return coroutine.wrap(function()
+            for x in s2() do
+                if not exlusions[x] then
+                    coroutine.yield(x)
+                end
+            end
+        end)
+    end
+end
+
+function maximum(stream)
+    local M = math.mininteger
+    for x in stream() do
+        M = math.max(M, x)
+    end
+    return M
+end
+
+local N = 100
+local A, B, C = 6, 9, 20
+
+local Xs = filter(range(0, N), function(x) return x  % A == 0 end)
+local Ys = filter(range(0, N), function(x) return x  % B == 0 end)
+local Zs = filter(range(0, N), function(x) return x  % C == 0 end)
+local sum = filter(apply(function(x, y, z) return x + y + z end, triple(Xs, Ys, Zs)), function(x) return x <= N end)
+
+print(maximum(exclude(sum, range(1, N))))