import Foundation

var str = "Hello, playground"
print(str)

let moop : Int = 69
let meep : Double = 11.11
let sum = moop + Int(meep)
let sum2 = Double(moop) + meep

let sentence = "\(moop) + 1 is 70"

var estr = "" //empty string
let isEmpty = estr.isEmpty

// Task : Write code to calculate and print the area of a square
let length : Int = 10
// Subtask : Calculate the area of a square
let area1 = length * length
// declare and initialise a variable to hold the length of the side of the square
let sideLength = 10
// declare a variable to hold the calculated area of the square
let area2 = length * sideLength
// assign the calculated value to the variable
let area3 = sideLength * sideLength

// Subtask : Print the area of the square
// print the calculated value
let message = "The area of a square of side length \(sideLength) is \(area1)"
print(message)

var girlsaregay : Bool = false

if (girlsaregay == false) {
    let one : Bool = true
    let two : Bool = false
    let passed = one || two

}

var temp : Double = 20
if temp > 20 {
    print("Too Hot")
} else {
    print("Too Cold")
}

var temperatureInFahrenheit = 90
if temperatureInFahrenheit <= 32 {
    print("It's very cold. Consider wearing a scarf.")
} else if temperatureInFahrenheit >= 86 {
    print("It's really warm. Don't forget to wear sunscreen.")
} else {
    print("It's not that cold. Wear a t-shirt.")
}

//Exercise 1
var kg = 15
let poundconv : Double = 2.2
let result = Double(kg)*poundconv
print("\(kg) kg is \(result) pounds")

//Exercise 2
print("The equation for a straight line is given by y = mx + c")
let m : Double = 3.2
let x : Double = 4.4
let c : Double = 10.8
print("The value of y given m(\(m)) x(\(x)) c(\(c)) is 24.88")

//Exercise 3
let DIST : Double = 4.0
let A : Double = 4.0
let Bp : Double = 3.5
let B : Double = 3.0
let Cp : Double = 2.5
let C : Double = 2.0
let Dp : Double = 1.5
let D : Double = 1.0
let F : Double = 0.0

print("Grade B+ is equal to a grade point of \(Bp)")

//Exercise 4
var year : Int = 2100
if year%4 == 0 {
    if year%100 == 0 && year%400 != 0 {
        print("Year \(year) is not a leap year")
    } else if year%100 == 0 && year%400 == 0 {
        print("Year \(year) is a leap year")
    } else if year%100 != 0 && year%400 != 0 {
        print("Year \(year) is a leap year")
    }
} else {
        print("Year \(year) is not a leap year")
    }
//since they appear every 4 years or so

//Exercise 5
var feeType = "SPR"

if feeType == "SC" {
    let TF : Double = 2900.00
    let SF : Double = 86.50
    let Total = TF+SF
    print("Singapore Citizens pay $\(Total) (Tuition Fee: $\(TF), Supplementary Fee: $\(SF)")
} else if feeType == "SPR" {
    let TF : Double = 5800.00
    let SF : Double = 116.50
    let Total = TF+SF
    print("Singapore Permanent Residents pay $\(Total) (Tuition Fee: $\(TF), Supplementary Fee: $\(SF)")
} else if feeType == "IS" {
    let TF : Double = 10400.00
    let SF : Double = 159.50
    let Total = TF+SF
    print("International Students pay $\(Total) (Tuition Fee: $\(TF), Supplementary Fee: $\(SF)")
}

//Exercise 6
var salary : Double = 160000.0
var tax : Double = 0.0
var extra : Double = 0.0
var eftax : Double = 0.0
if salary < 30000 {
    extra = salary - 20000
    tax = extra * 0.02
    eftax = tax / salary

} else if salary < 40000 {
    extra = salary - 30000
    tax = extra * 0.035 + 200
    eftax = tax / salary * 100

} else if salary < 80000 {
    extra = salary - 40000
    tax = extra * 0.07 + 550
    eftax = tax / salary * 100

} else if salary < 120000 {
    extra = salary - 80000
    tax = extra * 0.115 + 3350
    eftax = tax / salary * 100

} else if salary < 160000 {
    extra = salary - 120000
    tax = extra * 0.15 + 7950
    eftax = tax / salary * 100

} else if salary < 200000 {
    extra = salary - 160000
    tax = extra * 0.18 + 13950
    eftax = tax / salary * 100

} else if salary < 240000 {
    extra = salary - 200000
    tax = extra * 0.19 + 21150
    eftax = tax / salary * 100

} else if salary < 280000 {
    extra = salary - 240000
    tax = extra * 0.195 + 28750
    eftax = tax / salary * 100

} else if salary < 320000 {
    extra = salary - 280000
    tax = extra * 0.20 + 36550
    eftax = tax / salary * 100

} else if salary > 320001 {
    extra = salary - 32000
    tax = extra * 0.22 + 44550
    eftax = tax / salary * 100

}

print("For a salary of $\(salary), the income tax is $\(tax)")
print("The effective income tax rate is \(eftax)%")

//Question in class
let width = 10
let height = 25
let area = width*height
print("The area of rectangle with width \(width) and height \(height) is \(area)")

var num : Int = 4
if num%2 != 0 {
    print("\(num) is an odd number")
} else {
    print("\(num) is an even number")
}