func dfs(_ n:Int, _ m:Int, _ visited:inout [Bool], _ result:inout [Int], _ nums:[Int]) {
    if result.count == m {
        for n in result {
            print(n, terminator: " ")
        }
        print()
        return
    }

    for next in 0..<n {
        if !visited[next] {
            visited[next] = true
            result.append(nums[next])
            dfs(n,m,&visited,&result,nums)
            _ = result.popLast()
            visited[next] = false
        }
    }
}

if let input1 = readLine(), let NM:[Int] = input1.split(separator: " ").compactMap({Int($0)}) as? [Int], NM.count == 2 {
    let N:Int = NM[0]
    let M:Int = NM[1]

    if let input2 = readLine(), let nums:[Int] = input2.split(separator: " ").compactMap({Int($0)}) as? [Int], nums.count == N {
        var visited:[Bool] = Array(repeating: false, count: N)
        var result:[Int] = []
        dfs(N, M, &visited, &result, nums.sorted())
    }
}