diff --git a/cmd/gcd.go b/cmd/gcd.go
index ecf9d12..e49211e 100644
--- a/cmd/gcd.go
+++ b/cmd/gcd.go
@@ -42,6 +42,10 @@ func gcd(cmd *cobra.Command, args []string) {
 
 		z.GCD(&x, &y, &z, &w)
 
+		if !extended {
+			continue
+		}
+
 		for j, c := range bezouts {
 			if j == i {
 				bezouts[j].Set(&y)