diff --git a/cv1/program.c b/cv1/program.c
index 2f18d6c..699c0ce 100644
--- a/cv1/program.c
+++ b/cv1/program.c
@@ -12,8 +12,8 @@ int main() {
                 putchar(ch - 32); 
             } else if (ch >= 'A' && ch <= 'Z') {
                 putchar(ch + 32); 
-            } else {
-                putchar(ch); 
+            } else if (ch >= 32 && ch <= 127) {
+                putchar(9);
             }
         }
     }