diff --git a/main.cpp b/main.cpp
index fe6fb0d..f233c47 100644
--- a/main.cpp
+++ b/main.cpp
@@ -39,11 +39,13 @@ input_data() {
     for (i = 0; i < in.stroke.length(); i++) {
         if (isspace(in.stroke[i])) {
             cerr << "invalid input";
+            exit(0);
         }
     }
     if (in.stroke[0] == check2[0]) {
         if (in.stroke.length() != 7) {
             cerr << "invalid input";
+            exit(0);
         }
     }
     return in;