[Kotlin] - Pair

public data class Pair<out A, out B>(
    public val first: A,
    public val second: B
) : Serializable

var a = Pair(1, "짱구")
val b = Pair<Int, String>(second = "철수", first = 2)
val (c1, c2) = Pair(3, "유리")
val (d1, d2) = 4 to "훈발롬"

println("a.first = ${a.first} \t a.second = ${a.second}")

println("a = $a")

println("c.first = $c1 \t c.second = $c2")

// a.first = 1 	 a.second = 짱구
println("a.first = ${a.first} \t a.second = ${a.second}")
// a = (1, 짱구)
println("a = $a")

// b.first = 2 	 b.second = 철수
println("b.first = ${b.first} \t b.second = ${b.second}")
// b = (2, 철수)
println("b = $b")

// c.first = 3   	 c.second = 유리
println("c.first = $c1 \t c.second = $c2")

// d.first = 4 	     d.second = 훈발롬
println("d.first = $d1 \t d.second = $d2")

a = a.copy(first = 5, second = "돌")

fun main() {
    val pq = PriorityQueue<Pair<Int, Int>>()
    pq.offer(1 to 1)
    pq.offer(2 to 2)

    while (!pq.isEmpty()) {
        val cur = pq.poll()

        println(cur.first)
    }
}

// 방식 1
val pq = PriorityQueue<Pair<Int, Int>>(Comparator() { a, b -> a.first - b.first })

// 방식 2
val pq = PriorityQueue<Pair<Int, Int>> { a, b -> a.first - b.first }