diff --git a/gcd.py b/gcd.py
index 0f10da082d7..b496dca1d20 100644
--- a/gcd.py
+++ b/gcd.py
@@ -6,6 +6,7 @@
 b = int(input("Enter number 2 (b): "))
 
 i = 1
+gcd=-1
 while i <= a and i <= b:
     if a % i == 0 and b % i == 0:
         gcd = i