Operator	Name	Description
+	Addition	Adds together two values
-	Subtraction	Subtracts one value from another
*	Multiplication	Multiplies two values
/	Division	Divides one value by another
%	Modulus	Returns the division remainder
&&	Logical AND	Returns true if both statements are true
\|\|	Logical OR	Returns true if one of the statements is true
!	Logical NOT	Reverses the result — returns false if the result is true
in	Membership / Range check	Returns true if the left value is in a range (`x in 1..9`), an Array, a Set, or a Map key
??	Null coalescing	Returns the left side if non-null, otherwise the right side. E.g. `a?.get() ?? 100`
==	Equal	Compare values for equality
!=	Not equal	Returns true if values are not equal
>=	Greater than or equal	Returns true if left value is ≥ right value
<=	Less than or equal	Returns true if left value is ≤ right value
===	Strict equal	Compares pointer/reference equality (same memory address)
!==	Strict not equal	Returns true if the two objects are at different memory addresses
+=	Add and assign	Add right value to variable and assign the result
-=	Subtract and assign	Subtract right value from variable and assign the result
*=	Multiply and assign	Multiply variable by right value and assign the result
/=	Divide and assign	Divide variable by right value and assign the result

Example

val a = 10
val b = 3

// Arithmetic
println(a + b)   // 13
println(a - b)   // 7
println(a * b)   // 30
println(a / b)   // 3
println(a % b)   // 1

// Comparison
println(a == b)  // false
println(a != b)  // true
println(a >= b)  // true
println(a <= b)  // false

// Logical
val x = true
val y = false
println(x && y)  // false
println(x || y)  // true
println(!x)      // false

// Membership / Range check
val list = <Int>[1, 2, 3, 4, 5]
println(3 in list)   // true
println(3 in 1..9)   // true (inclusive range)
println(3 in 0..<3)  // false (exclusive upper)

// Null coalescing (??)
var s: String? = null
println(s ?? "default")  // default

// Assignment
var c = 5
c += 2            // 7
c -= 1            // 6
c *= 3            // 18
c /= 2            // 9
println(c)

// Strict / pointer comparison
val obj1 = 1
val obj2 = obj1
val obj3 = 1

println(obj1 === obj2) // true (same pointer)
println(obj1 !== obj3) // true (different pointer)

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