diff --git a/du6/program.c b/du6/program.c
index f144f8f..7dbc15c 100644
--- a/du6/program.c
+++ b/du6/program.c
@@ -10,9 +10,9 @@ typedef struct tree {
     struct tree *right;
 } Tree;
 
-int valid_db = 1;  // flag pre validitu databazy
+int valid_db = 1;
 
-// odstranit koncovy znak \n
+//odstranit koncovy znak
 void strip_newline(char *s) {
     int len = strlen(s);
     if (len > 0 && s[len-1] == '\n')
@@ -26,6 +26,7 @@ Tree* read_tree() {
     if (!fgets(buffer, SIZE, stdin))
         return NULL;
 
+    // prazdny riadok -> koniec
     if (strcmp(buffer, "\n") == 0)
         return NULL;
 
@@ -36,23 +37,23 @@ Tree* read_tree() {
 
     strcpy(node->value, buffer);
 
-    // list
+    // odpoved -> list
     if (buffer[0] == '*') {
         return node;
     }
 
-    // očakávame presne 2 potomkov
+    // inak nacitat oboch potomkov
     node->left = read_tree();
     if (!node->left) {
-        valid_db = 0;
+	valid_db = 0;
         free(node);
         return NULL;
     }
 
     node->right = read_tree();
     if (!node->right) {
-        valid_db = 0;
-        destroy_tree(node->left);
+        free(node->left);
+	valid_db = 0;
         free(node);
         return NULL;
     }
@@ -84,15 +85,19 @@ void run_system(Tree *node) {
 
     // list -> koniec
     if (!node->left && !node->right) {
-        printf("Koniec\n");
+	printf("Koniec\n");
         return;
     }
 
-    char c;
-    if (scanf(" %c", &c) != 1) {
-        printf("Nerozumiem\n");
-        return;
-    }
+    int c;
+
+    do {
+	    c = getchar();
+	    if (c == EOF) {
+		    printf("Koniec vstupu\n");
+		    return;
+	    }
+    } while (c=='\n'  || c=='\r' || c==' ' || c=='\t');
 
     if (c == 'a') {
         run_system(node->left);
@@ -106,14 +111,14 @@ void run_system(Tree *node) {
 int main() {
     Tree *root = read_tree();
 
-    // kontrola prázdneho alebo chybného stromu
+    // nepodarilo sa nacitat koren -> chyba
     if (!root || !valid_db) {
         printf("Expert z bufetu to vie.\n");
-        printf("Chybna databaza\n");
+	printf("Chybna databaza\n");
         return 0;
     }
 
-    // skontrolovat prazdny riadok po databaze
+    // skontrolovat prazdny riadok
     char buffer[SIZE];
     if (!fgets(buffer, SIZE, stdin) || strcmp(buffer, "\n") != 0) {
         printf("Koniec vstupu\n");