Fixed run_cmd to account for empty stdout

On Linux, a successful compile does not produce any standard out, which is what I was implicitly expecting. I added a dummy value for stdout if the command is successful, which ensures that even when the compiler produces no output, we still look like a success.

week4/day4.ipynb

@@ -455,7 +455,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 111,
+   "execution_count": 113,
    "id": "e42286bc-085c-45dc-b101-234308e58269",
    "metadata": {},
    "outputs": [],
@@ -477,7 +477,7 @@
     "def run_cmd(command_to_run):\n",
     "    try:\n",
     "        run_result = subprocess.run(command_to_run, check=True, text=True, capture_output=True)\n",
-    "        return run_result.stdout\n",
+    "        return run_result.stdout if run_result.stdout else \"SUCCESS\"\n",
     "    except:\n",
     "        return \"\"\n",
     "\n",
@@ -513,7 +513,7 @@
     "        elif my_platform == \"Linux\":\n",
     "            if os.path.isfile(\"./simple\"):\n",
     "                os.remove(\"./simple\")\n",
-    "            compile_cmd = [\"g++\", f\"{filename_base}.cpp\", \"-o\", f\"{filename_base}\" ]\n",
+    "            compile_cmd = [\"g++\", \"simple.cpp\", \"-o\", \"simple\"]\n",
     "            if run_cmd(compile_cmd):\n",
     "                if run_cmd([\"./simple\"]) == \"Hello\":\n",
     "                    my_compiler = [\"Linux\", \"GCC\", [\"g++\", f\"{filename_base}.cpp\", \"-o\", f\"{filename_base}\" ]]\n",