diff --git a/a1/program.c b/a1/program.c
index d31fba8..89e682c 100644
--- a/a1/program.c
+++ b/a1/program.c
@@ -2,6 +2,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <math.h>
+#include <ctype.h>
 
 int main () {
     char* input = (char*) calloc (100, sizeof(char));
@@ -14,6 +15,11 @@ int main () {
         if (!strcmp("\n", input))
             break;
 
+        for(int j = 0; input[j] != '\0' && input[j] != '\n'; j++)
+            if(!isdigit(input)){
+                printf("Nepodarilo sa nacitat polynom na %d mieste.\n", i+1);
+                return 0;
+            }
         if (i == 0){
             x = (double)strtod(input, &ptr);
         }