Read a $3-$character string from input into variable inputString. Declare a Boolean variable isValid and assign isValid with true if inputString does not contain any alphabetic characters. Otherwise, assign isValid with false.

Ex: If the input is $2$&$.,$ then isValid is assigned with true, so the output is:

Valid string

Ex: If the input is $7$y$1,$ then isValid is assigned with false, so the output is:

Invalid string

Note: Use getline$($cin$,$ inputString$)$ to read the entire line from input into inputString.