While (choose <= '0' || choose > '3'); switch

Question

While (choose <= '0' || choose > '3'); switch

(choose)
{
case '1':

cout << "how many customer accounts?";
cin >> choose;
for (i = 0; i < n; i++)
{
input ();
if (customer.payment > 0)
customer.acct_type =
(customer.payment < 0.1 * customer.oldbalance);
else
customer.acct_type = (customer.oldbalance > 0);
(customer.newbalance = customer.oldbalance - customer.payment);
writefile ();
}
main ();
case '2':

cout << "search by what?";
cout << "1 --- search by customer number";
cout << "2 --- search by customer name";
search ();
main ();
}