Swift Arithmetic Operators

Basic Arithmetic Operators

let sum = 15 + 25  // 40
let total = 3.5 + 2.1 // 5.6

let diff = 20 - 8   // 12
let result = 10.5 - 3.2 // 7.3

let product = 6 * 7  // 42
let area = 4.5 * 2.0 // 9.0

let quotient = 15 / 3  // 5
let decimal = 7.0 / 2.0 // 3.5

🔹 Basic Arithmetic Operations

Perform fundamental math operations with Swift:

// Addition
let a = 10
let b = 5
let sum = a + b          // 15

// Subtraction
let difference = a - b   // 5

// Multiplication
let product = a * b      // 50

// Division
let quotient = a / b     // 2

// Working with decimals
let price1 = 19.99
let price2 = 24.50
let totalPrice = price1 + price2  // 44.49

print("Sum: \(sum)")
print("Product: \(product)")
print("Total price: $\(totalPrice)")

🔹 Remainder Operator (%)

The remainder operator returns what's left after division:

// Remainder (modulo) operator
let remainder1 = 10 % 3   // 1 (10 ÷ 3 = 3 remainder 1)
let remainder2 = 15 % 4   // 3 (15 ÷ 4 = 3 remainder 3)
let remainder3 = 20 % 5   // 0 (20 ÷ 5 = 4 remainder 0)

// Checking if a number is even or odd
let number = 17
let isEven = number % 2 == 0
let isOdd = number % 2 == 1

// Practical example: cycling through values
let items = ["Red", "Green", "Blue"]
let index = 7
let selectedItem = items[index % items.count]  // "Green" (7 % 3 = 1)

print("17 % 2 = \(number % 2)")
print("Is 17 even? \(isEven)")
print("Selected item: \(selectedItem)")

🔹 Unary Minus Operator

The unary minus operator changes the sign of a number:

// Unary minus operator
let positiveNumber = 42
let negativeNumber = -positiveNumber  // -42

// Toggling signs
var temperature = 25
temperature = -temperature  // -25

// Using with expressions
let x = 10
let y = 5
let result = -(x + y)  // -15

// Double negative
let originalValue = -30
let positiveValue = -originalValue  // 30

print("Negative number: \(negativeNumber)")
print("Temperature: \(temperature)°C")
print("Result: \(result)")
print("Positive value: \(positiveValue)")

🔹 Compound Assignment Operators

Combine arithmetic operations with assignment:

// Compound assignment operators
var score = 100

// Addition assignment
score += 25    // score = score + 25 (now 125)

// Subtraction assignment
score -= 10    // score = score - 10 (now 115)

// Multiplication assignment
score *= 2     // score = score * 2 (now 230)

// Division assignment
score /= 5     // score = score / 5 (now 46)

// Remainder assignment
score %= 10    // score = score % 10 (now 6)

// Working with strings
var message = "Hello"
message += " World"    // "Hello World"
message += "!"         // "Hello World!"

print("Final score: \(score)")
print("Message: \(message)")

🔹 Operator Precedence

Swift follows mathematical order of operations:

// Operator precedence examples
let result1 = 2 + 3 * 4        // 14 (not 20)
let result2 = (2 + 3) * 4      // 20
let result3 = 10 - 6 / 2       // 7 (not 2)
let result4 = (10 - 6) / 2     // 2

// Complex expression
let a = 5
let b = 3
let c = 2
let complex = a + b * c - 4    // 5 + 6 - 4 = 7

// Using parentheses for clarity
let clear = (a + b) * (c - 1)  // (5 + 3) * (2 - 1) = 8

print("2 + 3 * 4 = \(result1)")
print("(2 + 3) * 4 = \(result2)")
print("Complex result: \(complex)")
print("Clear result: \(clear)")