diff --git a/du3/program.c b/du3/program.c
index 43853eb..3a65bc4 100644
--- a/du3/program.c
+++ b/du3/program.c
@@ -100,8 +100,8 @@ int main()
 
                 else if (strBuffer[i] == '+' || strBuffer[i] == '-' || strBuffer[i] == '/' || strBuffer[i] == '*')
                 {
-                    //predbezna kontrola, ze ci sme doteraz daco vobec nacitavali
-                    if (op1 == 'N' || strBuffer[0] == '\0')
+                    //predbezna kontrola, ak uz operator mame tak vyhod chybu pri druhom pokuse o nacitanie
+                    if (op1 != 'N')
                     {
                         isLineInvalid = true;
                     }