Make a simple currency converter for 3 currencies

Question :  You are required to write a program for Currency Exchange rates. The basic idea is that user/reader will be able to interchange different currencies using our program. User will have three options i.e. Pakistani Rupees, US Dollars, and Euro. In the end of the program, user should be asked if he/she wants to make another conversion. If user presses y then the whole program should start again. If user presses n then the program should terminate.

 #include <iostream>  
 using namespace std;  
 void main()  
 {  
      int amount=0;  
      char choice1, choice2, choice3='Y';  
      while (choice3=='Y')  
      {  
           cout<<"Select the currencies that you want to exchange\n";  
           cout<<" - Enter R for Pakistani Rupees\n";  
           cout<<" - Enter E for Euro\n";  
           cout<<" - Enter D for Dollar\n"<<endl;  
           cout<<"Please select the currency that you want to convert"<<endl;  
           cin>>choice1;  
           cout<<"Please enter the currency that you want to convert into"<<endl;  
           cin>>choice2;  
           cout<<"Enter Amount: ";  
           cin>>amount;  
           if ( choice1=='R' && choice2=='E')  
           {  
                //division of input rupees by 112 to convert into euros  
                cout<<amount <<" Rupees = "<<amount/112<<" Euros"<<endl;    
           }  
           if ( choice1=='R' && choice2=='D')  
           {  
                //division of input rupees by 84 to convert into dollars  
                cout<<amount <<" Rupees = "<<amount/84<<" Dollars"<<endl;   
           }  
           if ( choice1=='E' && choice2=='R')  
           {  
                //multiplication of input Euros by 112 to convert into rupees  
                cout<<amount <<" Euros = "<<amount*112<<" Rupees"<<endl;   
           }  
           if ( choice1=='E' && choice2=='D')  
           {  
                //multiplication of input Euros by 1.33 to convert into dollars  
                cout<<amount <<" Euros = "<<amount*1.33<<" Dollars"<<endl;   
           }  
           if ( choice1=='D' && choice2=='R')  
           {  
                //multiplication of input dollars by 84 to convert into rupees  
                cout<<amount <<" Dollars = "<<amount*84<<" Rupees"<<endl;   
           }  
           if ( choice1=='D' && choice2=='E')  
           {  
                //division of input dollars by 1.33 to convert into euros  
                cout<<amount <<" Dollars = "<<amount/1.33<<" Euros"<<endl;   
           }  
           cout<<"Do you want to make another conversion? ( Y/N ) :";  
           cin>>choice3;  
      }  
      cout<<"Goodbye :) "<<endl;  
 }