why i cant instantiate objects inside a switch-case block

Question

my code has 3 classes n_hexa,n_octa,n_bin. The code is here

switch(choice)
{
case 1: cin>>n; 
 n_hexa nx(n);
        break;
case 2: cin>>n; 
 n_octa no(n);
        break;
case 3: cin>>n;
 n_bin nb(n);
        break;
}

on compiling it gives a message "crosses initialisation of n_hexa" for line of n_octa

Answer 1

If you want to have temporary objects inside a case, you'll need to scope them properly.

switch(choice)
{
    case 1:
    {
         cin>>n; 
         n_hexa nx(n);
         break;
    }
    case 2:
    {
         cin>>n; 
         n_octa no(n);
         break;
    }
    case 3:
    {
         cin>>n;
         n_bin nb(n);
         break;
    }
}

Answer 2

Try declaring the variables above the switch command:

n_hexa nx;
n_octa no;
n_bin nb;
switch(choice) {
    case 1:
        cin>>n;
        nx(n);
        break;
...