Conditionals in Kotlin

// If expression
val max = if (a > b) a else b

// If-else chain
val result = if (score >= 90) {
    "A"
} else if (score >= 80) {
    "B"
} else if (score >= 70) {
    "C"
} else {
    "F"
}

// When expression (like switch)
when (x) {
    1 -> println("One")
    2 -> println("Two")
    3, 4 -> println("Three or Four")
    in 5..10 -> println("Between 5 and 10")
    !in 10..20 -> println("Not between 10 and 20")
    is String -> println("It's a string")
    else -> println("Unknown")
}

// When as expression
val description = when (val code = getCode()) {
    200 -> "OK"
    404 -> "Not Found"
    500 -> "Server Error"
    else -> "Unknown code: $code"
}