설탕 배달(백준)

package com.example.algorithm

import java.io.BufferedReader
import java.io.BufferedWriter
import java.io.InputStreamReader
import java.io.OutputStreamWriter
import java.util.Collections.max
import java.util.Collections.min


fun main(){

    val br = BufferedReader(InputStreamReader(System.`in`))
    val bw = BufferedWriter(OutputStreamWriter(System.`out`))

    val input = br.readLine().toInt()
    val results = mutableListOf<Int>()


    for (i in 0 until (input/5)+1){
        for(j in 0 until (input/3)+1){
            val result = i*5 + j*3
            if(result == input){
                results.add(i+j)
            }
        }
    }

    if(results.size==0){
        bw.write(String.format("%d",-1))
    }else{
        bw.write(String.format("%d",min(results)))
    }


    bw.flush()
    bw.close()
    br.close()
}

그냥 단순하게 모든 경우의 수를 대입해서 계산해주었다.