pakages

/*A mobile phone service provider has three different subscription packages for its 
customers: 
Package A: For $39.99 per month 450 minutes are provided. Additional minutes are 
$0.45 per minute. 
Package B: For $59.99 per month 900 minutes are provided. Additional minutes are 
$0.40 per minute. 
Package C: For $69.99 per month unlimited minutes provided. 
Write a program that calculates a customer’s monthly bill. It should ask which package 
the customer has purchased and how many minutes were used. It should then display 
the total amount due. 
Input Validation: Be sure the user only selects package A, B, or C  */
#include <iostream>
#include<iomanip>
using namespace std;
int main() {
    int num,opt,num1;
   char pakage1,pakage2,pakage3;
   do{
  cout<<"choose a pakage: "<<endl<<"1.pakage 1"<<endl<<"2.pakage 2"<<endl<<"3.pakage 3"<<endl;
   cin>>opt;
   
   switch(opt){
       case 1:
            cout<<"you chose pakage 1: "<<endl;
            break;
        case 2:
            cout<<"you chose  pakage 2: "<<endl;
            break;
       case 3:
             cout<<"you chose pakage 3: "<<endl;
             break;
         default: cout<<"invalid input re-enter the number: "<<endl;
            
           
   }
   } 
   while(opt<1 || opt>4);
      
  cout<<"if u wanna choose more pakages press -1 "<<endl;
    cin>>num1;       
    return 0;
}