diff --git a/backend.py b/backend.py
index 1d07fba..38940b7 100644
--- a/backend.py
+++ b/backend.py
@@ -2,3 +2,7 @@ def calculate(height, wight):
     result = wight / height ^ 2
     return result
 
+def user_input_check(height, wight):
+    if height.isdigit() and wight.isdigit():
+        if height != 0 and wight != 0:
+            return True