fun main(args: Array<String>) {
    val line = readLine()
    val nums = line!!.split(" ").map { it.toInt() }
    val ans = solve(nums)
    print(ans)
}

fun solve(nums: List<Int>): String {
    return if (nums[0] <= nums[1]) {
        Safe.unsafe.name
    } else {
        Safe.safe.name
    }
}

enum class Safe {
    unsafe,
    safe
}