無止盡的Coding地獄

#include <stdio.h>
#include <stdlib.h>

int main ()
{
    float b_balance, n_balance, charges, credits, cred_limit;
    int accountnum;
    
    while( accountnum != -1 )
    {
           printf("Enter account number (-1 to end): ");
           scanf("%d",&accountnum);
           if ( accountnum == -1 )  break;
           else
           {
               printf("Enter beginning balance: ");
               scanf("%f",&b_balance);
               printf("Enter total charges: ");
               scanf("%f",&charges);
               printf("Enter total credits: ");
               scanf("%f",&credits);
               printf("Enter credit limit: ");
               scanf("%f",&cred_limit);
               n_balance = ( b_balance + charges - credits );
               
               if ( n_balance > b_balance )  
               {
                 printf("Account:\t%d\n",accountnum);
                 printf("Credit limit:\t%f\n",cred_limit);
                 printf("Balance:\t%f\n",n_balance);
                 printf("Credit Limit Exceed.\n");
               }
           }
    }
    system("PAUSE");
    return 0;
}