2.4 while, for - ericbykim/kotlin-in-action GitHub Wiki
while
while (cond) {
/* ... */
}
do {
/* ... */
} while (cond)
for
- λ²μ(range)λ₯Ό μ¬μ©νλ€.
..
, downTo
, step
, until
val oneToTen = 1..10 // 1~10 1,10 ν¬ν¨
fun fizzbuzz(i: Int) = when {
i%15 == 0 -> "FizzBuzz"
i%3 == 0 -> "Fizz"
i%5 == 0 -> "Buzz"
else -> "$i"
}
for (i in 1..100) { // 1, 100 ν¬ν¨
print(fizzbuzz(i))
}
for (i in 100 downTo 1 step 2) {
print(fizzbuzz(i))
}
for (i in 0 until 100) { // 100 λ―Έν¬ν¨
print(fizzbuzz(i))
}
val myMap = TreeMap<Char, String>()
for (c in 'A'..'F') {
mapMap[c] = Integer.toBinaryString(c.toInt())
}
for ((letter, binary) in myMap) {
}
val list = arrayListOf("10", "11", "1001")
for ((index, element) in list.withIndex()) {
}
in
in
κ°μ΄ λ²μμ μνλμ§ κ²μ¬
!in
κ°μ΄ λ²μμ μνμ§ μλμ§ κ²μ¬
fun isLetter(c: Char) =
c in 'a'..'z' || c in 'A'..'Z' // 'a'<=c && c<='z'λ‘ λ³νλλ€.
fun isNotDigit(c: Char) =
c !in '0'..'9'
fun test(c: Char) = when(c) {
in '0'..'9' -> "digit"
in 'a'..'z', in 'A'..'Z' -> "letter"
else -> "don't know"
}
- java.lang.Comparable μΈν°νμ΄μ€λ₯Ό ꡬνν ν΄λμ€λ λ²μλ₯Ό λ§λ€ μ μλ€.
"Kotlin" in "Java".."Scala" // true
"Kotlin" in setOf("Java","Scala") // false