Given a string variable s that has already been declared, write some code that repeatedly reads a value from standard input into s until at last a "y" or "y"or "n" or "n" has been entered.

The code to this question can be given as:

Code:

while ((s!="Y" && s!="y" && s!="N" && s!="n"))  //loop for check condition

{

cin >> s;  //insert value

}

Explanation:

The description of the following code:

In this code, we use a string variable s that has been to define in question. In code, we use a while loop. It is an entry control loop in loop we check variable s value is not equal to "y", "Y", "n" and "N".   In the loop we use AND operator that checks all value together. If this is true So, we insert value-form user input in string variable that is "s".

Answer (b) the meter will display a negative sign;