## strlenprog

### Instructions

-   Write a program that counts the characters of a `string` and that returns that value.

-   If the program receives more than one or no arguments it must not print anything.

### Expected output :

```console
student@ubuntu:~/piscine-go/strlenprog$ go build
student@ubuntu:~/piscine-go/strlenprog$ ./strlenprog "hello" | cat -e
5$
student@ubuntu:~/piscine-go/strlenprog$ ./strlenprog
student@ubuntu:~/piscine-go/strlenprog$
student@ubuntu:~/piscine-go/strlenprog$ ./strlenprog "hello" "how are you"
student@ubuntu:~/piscine-go/strlenprog$
```