Update app.py

app.py

@@ -5,9 +5,14 @@ import re
 
 def load_cpp_file(file):
     text = file.name
-    with open(text, 'r', encoding='utf-8') as f:
-        content = f.read()
-    return content
+    if file is None:
+        return ""
+    try:
+        with open(text, 'r', encoding='utf-8') as f:
+            content = f.read()
+        return content
+    except:
+        return ""
 
 def Evaluate_Code(code, method):
     if method == "No Format":