ATM Machine

Context

Is it an ATM Machine? Is it an AT Machine? Is it an ATM? Who's for certain

Snippet

#include <stdio.h>

int main() {
    int pin,
        selection;

    double balance = 2025.02;

    printf("Enter PIN: ");
    scanf("%d", &pin);
    if (pin == 2160) { // Login success
        printf("\nSuccessful login! Select option");
        printf("\n(1 - check balance, 2 - withdraw money, 3 - deposit money): ");
        scanf("%d", &selection);
        switch (selection) {
            double amount;
            case 1:
                // Check Balance case

                printf("\nCurrent balance = $%.2lf", balance);
                break;
            case 2:
                // Withdraw Amount case

                printf("\nEnter amount to withdraw: ");
                scanf("%lf", &amount);

                if (amount < 0) { // Amount validity check
                    printf("\nInvalid withdrawal amount $%.2lf", amount);
                } else if (amount > balance) { // Amount validity check
                    printf("\nCannot withdraw $%.2lf--balance too low", amount);
                } else { // Withdrawal execution
                    balance -= amount;
                    printf("\nWithdrawing $%.2lf, new balance = $%.2lf", amount, balance);
                }
                break;
            case 3:
                // Deposit Amount case
                printf("\nEnter amount to deposit: ");
                scanf("%lf", &amount);

                if (amount <= 0) { // Amount validity check
                    printf("\nInvalid deposit amount $%.2lf", &amount);
                } else { // Depsoit execution
                    balance += amount;
                    printf("\nDepositing $%.2lf, new balance = $%.2lf", amount, balance);
                }
                break;
            default:
                // Selection validity

                printf("\nInvalid option %d", selection);
        }
    } else { // Fails login
        printf("\nInvalid PIN--cannot login!");
    }
    printf("\n");
}