https://www.acmicpc.net/problem/3460
1) int형 값을 n진수변환해주려면 String(int, radix: n)을 사용
2) string을 뒤집으려면 reversed()함수를 사용
import Foundation
let input = readLine()!
let count = Int(input)!
for _ in 0..<count {
let num = Int(readLine()!)!
let binary = String(num, radix: 2 )
for (i,v) in binary.reversed().enumerated() {
if v == "1" {
print(i, terminator: " ")
}
}
}