A logistics developer is writing a container location system for a shipping terminal. The terminal layout utilizes a 4 x 4 grid consisting of sixteen storage zones.
In the control application, a storage zone is referenced by a column letter followed by a row number. For example, zone Q7 in Figure 1 contains a shipping container marked with X.
Figure 2 shows a segment of a C# program designed to retrieve and initially filter the zone reference entered by an operator.
The zone reference is valid if and only if:
- there are exactly two characters
- the first character is P, Q, R, or S
- the second character is 5, 6, 7, or 8.
Figure 1
Figure 2
bool valid = false;
while (valid == false) {
string zone = "";
while (zone.Length != 2) {
Console.Write("Enter container zone (e.g. Q7): ");
zone = Console.ReadLine();
zone = zone.ToUpper();
}
}
Extend the program from Figure 2 so it performs the remaining validation checks necessary to guarantee a valid zone reference is entered.
Your extended program must:
- use the variable
valid - repeat the steps until a valid zone reference is entered:
- prompt the operator to enter a zone reference
- output an appropriate error message if the entered zone reference is not valid.
You should use meaningful variable name(s) and C# syntax in your answer.