let expense = (amount) => {
  AvailableBalance = AvailableBalance - amount;
  return `Expense = ${amount}$  Current Balance = ${AvailableBalance}$`;
};
let deposit = (amount) => {
  AvailableBalance = AvailableBalance + amount;
  return `Deposit = ${amount}$  Current Balance = ${AvailableBalance}$`;
};
let index = 0;
var r1 = require('readline');
var prompts = r1.createInterface(process.stdin, process.stdout);
let i = 0;
while (i === 0)
{
prompts.question('Do you want to deposit or withdrow? Enter d or w : ', function(input) {
if (input === 'd') {
  prompts.question('Enter amount : ', function(amount) {
    index = index + 1;
    console.log(deposit(parseInt(amount)));
    process.exit();
  });
}
else if ( input === 'w') {
  prompts.question('Enter amount', function(amount) {
    index = index + 1;
      console.log(expense(parseInt(amount)));
    process.exit();
});
}
else if ( input === 'end') {
  i = 1;
}
});
}