[백준] 부분수열의 합

https://www.acmicpc.net/problem/1182

 

fun main() = with(Scanner(System.`in`)) {
    val n = nextInt()
    val s = nextInt()
    val arr = Array<Int>(n) { 0 }
    for (i in 0 until n) {
        arr[i] = nextInt()
    }

    var sCount = 0
    fun total(cur : Int , sum : Int){
        if(cur == n){
            if(sum == s) sCount++
            return

        }
        total(cur + 1, sum)
        total(cur + 1, sum + arr[cur])
    }

    total(0,0)
    if(s == 0) sCount--
    println(sCount)
}