diff --git a/main.py b/main.py
index 376d083..14d7902 100755
--- a/main.py
+++ b/main.py
@@ -85,17 +85,17 @@ def calcul(left: int, right: int, res: int, operation='+'):
 
     if operation in ['+', 'add', 'sum']:
         result = left + right
-    if operation in ['-', 'sub']:
+    elif operation in ['-', 'sub']:
         result = left - right
-    if operation in ['*', 'mul', 'prod']:
+    elif operation in ['*', 'mul', 'prod']:
         result = left * right
-    if operation in ['/', 'div']:
+    elif operation in ['/', 'div']:
         result = left / right
-    if operation in ['&', 'and']:
+    elif operation in ['&', 'and']:
         result = left & right
-    if operation in ['|', 'or']:
+    elif operation in ['|', 'or']:
         result = left | right
-    if operation in ['^', 'xor']:
+    elif operation in ['^', 'xor']:
         result = left ^ right
     else:
         result = left % right