diff --git a/lib/intcode/assembler.ex b/lib/intcode/assembler.ex
index b37269d..0e3915c 100644
--- a/lib/intcode/assembler.ex
+++ b/lib/intcode/assembler.ex
@@ -214,6 +214,11 @@ defmodule Assembler do
                  add #{a}, $#{dest}, #{dest}
                  """
 
+  assemble_macro ["not", src, dest],
+                 """
+                 sub 1, #{src}, #{dest}
+                 """
+
   assemble_macro ["cle", a, b, dest],
                  """
                    clt #{a}, #{b}, #{dest}
@@ -225,16 +230,14 @@ defmodule Assembler do
 
   assemble_macro ["cgt", a, b, dest],
                  """
-                   clt #{a}, #{b}, #{dest}
-                   jnz $#{dest}, false
-                   ceq #{a}, #{b}, #{dest}
-                   jnz $#{dest}, false
-                   mov 1, #{dest}
-                   jmp end
+                 cle #{a}, #{b}, #{dest}
+                 not $#{dest}, #{dest}
+                 """
 
-                 false:
-                   mov 0, #{dest}
-                 end:
+  assemble_macro ["cge", a, b, dest],
+                 """
+                 clt #{a}, #{b}, #{dest}
+                 not $#{dest}, #{dest}
                  """
 
   @doc """
@@ -262,9 +265,9 @@ defmodule Assembler do
     iex> Assembler.parse_params(["$1", "2", "3"], [:read, :read, :write])
     {[1, 2, 3], 1000}
     iex> Assembler.parse_params(["$label", "2", "3"], [:read, :read, :write])
-    {[{:expr, "label"}, 2, 3], 1000}
+    {[{:expr, ["label"]}, 2, 3], 1000}
     iex> Assembler.parse_params(["1", "label", "3"], [:read, :read, :write])
-    {[1, {:expr, "label"}, 3], 1100}
+    {[1, {:expr, ["label"]}, 3], 1100}
   """
   def parse_params(params, param_types) do
     params
diff --git a/test/intcode/assembler_test.exs b/test/intcode/assembler_test.exs
index 4929dda..1bd3005 100644
--- a/test/intcode/assembler_test.exs
+++ b/test/intcode/assembler_test.exs
@@ -28,6 +28,31 @@ defmodule AssemblerTest do
     assert assemble("mov 1, 2") == [1101, 0, 1, 2]
     assert assemble("jmp 2") == [1105, 1, 2]
     assert assemble("sub 5, 3, res\nres: 0") == [1102, 3, -1, 8, 101, 5, 8, 8, 0]
+    assert assemble("not 4, 4") == [1102, 4, -1, 4, 101, 1, 4, 4]
+    assert assemble("cle 1, 2, res\nres: 0") == [1107, 1, 2, 11, 1005, 11, 11, 1108, 1, 2, 11, 0]
+
+    assert assemble("cgt 1, 2, res\nres: 0") == [
+             1107,
+             1,
+             2,
+             19,
+             1005,
+             19,
+             11,
+             1108,
+             1,
+             2,
+             19,
+             1002,
+             19,
+             -1,
+             19,
+             101,
+             1,
+             19,
+             19,
+             0
+           ]
   end
 
   test "assembles simple program" do