some one 0 Junior Poster

hi every1
i want to ask what wrong with my program
it all work allright just the zakat function when i run the program the output is garpege
here is the code

#include  <iostream.h>
#include  <conio.h>
#include <stdlib.h>

class Customer {

   private:
      char name[20];
      char address[30];
      char city[20];
      char pcode[6];
      float acc_bal;
double zak;
   public:
      Customer:: Customer() {              // constructor
         acc_bal = 0.00;
      }

      void getdata() {
         cout << "\nEnter your name: ";    cin >> name;
         cout << "\nEnter your address: ";   cin >> address;
         cout << "\nEnter your city: ";      cin >> city;
         cout << "\nEnter your postal code: ";    cin >> pcode;
         cout << "\nEnter current account balance: ";    cin >> acc_bal;
      }

      void deposit() {
         float dep;
         cout << "\nEnter amount to be deposited: ";
         cin >> dep;
         acc_bal += dep;
      }

      void withdraw() {
         float wdraw;
         cout << "\nEnter amount to be withdrawn: ";    cin >> wdraw;
         acc_bal -= wdraw;
      }
	  void zakat()
	  {
		  
		  zak= (acc_bal*2.5)/100;
	  }

      void showdata() {
         cout << "Name: " << name;
         cout << "\nAddress: " << address;
         cout << "\nCity: " << city;
         cout << "\nPostal Code: " << pcode;
         cout << "\nAccount Balance: $" << acc_bal << endl;
		 cout<<"Zakat is: "<<zak<<endl;
      }

};

int main() {

   char choice;
   bool flag =0;
   int count = 0;
   int recnum;
   Customer cust[10];

   while (flag == false) {
      cout << "\t\t\n\n" << "Main Menu";
      cout << "\t\n\n" << "Select by letter:";
      cout << "\t\n" << "a - Add a customer.";
      cout << "\t\n" << "d - Deposit money.";
      cout << "\t\n" << "w - Withdraw money.";
      cout << "\t\n" << "s - Show Account Information.";
      cout << "\t\n" << "q - Quit Application.\n\n";
      cout << "\t" << "Choice: ";
      cin>>choice ;
      switch(choice) {
         case 'a':
            system("cls");
            if (count > 10) {
               cout << "Can't add anymore records. Press any key to return to main menu.";
               getche();
               break;
            }
            count += 1;
            cust[count].getdata();
            system("cls");
            break;

         case 'd':
            system("cls");
            cout << "\nEnter customer number: ";
            cin >> recnum;
            cust[recnum].deposit();
            system("cls");
            break;

         case 'w':
            system("cls");
            cout << "\nEnter customer number: ";
            cin >> recnum;
            cust[recnum].withdraw();
            system("cls");
            break;

         case 's':
            system("cls");
            cout << "\nEnter customer number: ";
            cin >> recnum;
            cust[recnum].showdata();
            getche();
            system("cls");
            break;

         case 'q':
            flag = 1;
            break;

         default:
            cout << "\nInvalid selection. Press a key to return to main menu.";
            getche();
      }

      if (flag == true) {
         break;
      }

   }
   return 0;
}