diff --git a/cv7/program.c b/cv7/program.c
index 8b95c56..e779976 100644
--- a/cv7/program.c
+++ b/cv7/program.c
@@ -15,7 +15,7 @@ struct tree
 struct tree* read_tree()
 {
     char buffer[SIZE];
-    if (!fgets(buffer, SIZE, stdin) || buffer[0] == '\n')
+    if (!fgets(buffer, SIZE, stdin) || buffer[0] == '\n' || buffer[0] == '\0')
     {
         return NULL;
     }
@@ -136,6 +136,11 @@ void interact(struct tree *node, int fstenter)
 int main()
 {
     struct tree *root = read_tree();
+    if(root == NULL)
+    {
+        printf("Chybna databaza\n");
+        return 0;
+    }
     //getchar();
     int leafs = count_leaf_nodes(root);
     if(leafs == 0)