# If and else

If and else are two expressions that are used to check if variables are true or not.

An example of if and else is withdrawal at an ATM. Will a user get money from a ATM if he wants to withdrawal \$ 50 from ATM, and have \$ 100 in his account?

To solve this problem, we must:

• Start a `Scanner` for input.
• Create a variable with the bank account balance.
• Ask how much the user wants to withdraw.
• Calculating the difference between the available balance and the withdraw.
• Give money or write a error message.
`package ifandelse;import java.util.Scanner;public class Ifandelse {        public static void main(String[] args) {                // Import scanner                Scanner scanner = new Scanner (System.in);                                // Variables money in bank                double balance = 100;                                 // Ask for withdraw                System.out.println("Enter withdrawal amount: ");                double withdrawal = scanner.nextDouble();                                // Calculate if it is ok                double calculation = balance-withdrawal;                                // Check if calculation is ok                if(calculation > -1){                        System.out.println("Here is your money.");                }                else{                        System.out.println("You do not have enough money on bank account.");                }                        }}`

We check in the `if` and `else` if the difference between account balance and the withdrawal is greater than the number -1.
An example is if want to withdraw \$ 60, and the balance is \$ 100 the formula will be:

double calculation = balance-withdrawal;
calculation = 100-60;

## Assignments

1. Extend the program above to view balances before and after the user has withdraw money.

2. Create a program that proposes waxing for cross-country skis. Ask user for temperature outside, and provide suggestions:
red wax for +4°C to -3°C
and
blue wax for -4°C to -15°C.

3. Create an ATM that printer a menu first. In the menu you can choose to withdraw money or to show balance.

4. In Counter Strike, you can buy different weapons and equipment. Create a program which allows the user to purchase various weapons and equipment from a menu. First, create a variable with available amount of money, also let the user buy equipment on the basis of how much money user has.

Available guns should be:
glock
usp
p228
deagle
elite
fn57

Available shotguns should be:
m3
xm1014

Available machine guns should be:
mac10
tmp
mp5
ump45
p90

Available rifles should be:
galil
ak47
sg552
famas
m4a1
aug

Available snipers should be:
g3sg1
sg550
scout
awp

Available machine rifles should be:
m249

Available equipment must be:
defuser
vest
vesthelm
flashbang
2flashbang
smoke
nvgs