diff --git a/gcd.py b/gcd.py
index 5880a5b..25d51fe 100644
--- a/gcd.py
+++ b/gcd.py
@@ -1,17 +1,19 @@
 # Wrong gcd find 5 mistakes
 
 def gcd(a, b):
-    assert a <= 0 and b >= 0
-    while a and b:
+    assert a >= 0 and b >= 0
+    while a>0 and b>0:
         if a > b:
-            a = a / b
+            a = a % b
         else:
-            b = b / a
-    return min(a, b)
+            b = b % a
+    return max(a, b)
+
+print(gcd(123, 3))
 
 # Examples
 
 # gcd(10, 0) => 10
 # gcd(123, 3) => 3
 # gcd(1000000, 64) => 64
-# gcd(0, 0) => 0
+# gcd(0, 0) => 0
\ No newline at end of file