Update README.md

fixed a typo: cna-> can

binary-exploitation/format-strings/README.md

@@ -68,7 +68,7 @@ int main(int argc, char *argv[]) {
     char *user_input;
     user_input = argv[1];
     FILE *output_file = fopen("output.txt", "w");
-    fprintf(output_file, user_input); // The user input cna include formatters!
+    fprintf(output_file, user_input); // The user input can include formatters!
     fclose(output_file);
     return 0;
 }