diff --git a/ex14.c b/ex14.c
index 6eeacbe..403769b 100644
--- a/ex14.c
+++ b/ex14.c
@@ -1,22 +1,23 @@
 #include <stdio.h>
 #include <ctype.h>
+#include <string.h>
 
-void print_letters(char arg[]);
+void print_letters(char arg[], int nchars);
 
 void print_arguments(int argc, char *argv[])
 {
     int i = 0;
 
     for(i = 0; i < argc; i++) {
-        print_letters(argv[i]);
+        print_letters(argv[i], strlen(argv[i]));
     }
 }
 
-void print_letters(char arg[])
+void print_letters(char arg[], int nchars)
 {
     int i = 0;
 
-    for (i = 0; arg[i] != '\0'; i++) {
+    for (i = 0; i < nchars; i++) {
         char ch = arg[i];
 
         if(isalpha(ch) || isblank(ch)) {