Kotlin Operators

Arithmetic Operators

Kotlin supports the standard arithmetic operators +, -, *, /, and % (remainder), which work on all numeric types. Division between two integers truncates toward zero, so understanding the operand types matters as much as the operator itself.

fun main() {
    val a = 17
    val b = 5

    println("Sum: ${a + b}")
    println("Difference: ${a - b}")
    println("Product: ${a * b}")
    println("Integer division: ${a / b}")
    println("Remainder: ${a % b}")
}

Comparison Operators

Comparison operators (==, !=, <, >, <=, >=) evaluate to a Boolean. Unlike Java, Kotlin's == calls the equals() method for objects, so it checks structural equality rather than reference identity by default; use === to compare references directly.

fun main() {
    val x = 10
    val y = 20

    println(x == y)       // false
    println(x != y)       // true
    println(x < y)        // true
    println(x >= y)       // false

    val name1 = "Kotlin"
    val name2 = "Kotlin"
    println(name1 == name2)   // true, structural equality
}

Logical Operators

Logical operators combine Boolean expressions: && (AND) is true only when both sides are true, || (OR) is true when at least one side is true, and ! negates a Boolean. Kotlin evaluates && and || lazily, so the right-hand side is skipped once the result is already determined.

• Arithmetic operators (*, /, %) bind tighter than + and -
• Comparison operators are evaluated after arithmetic operators
• && binds tighter than ||, so a || b && c means a || (b && c)
• Use parentheses whenever precedence is not immediately obvious to a reader

fun main() {
    val age = 25
    val hasLicense = true

    val canDrive = age >= 18 && hasLicense
    val needsSupervision = age < 18 || !hasLicense

    println("Can drive alone: $canDrive")
    println("Needs supervision: $needsSupervision")
}