Slides.scala

package Main

import java.io.{FileInputStream, FileOutputStream}

import scala.io.StdIn


object Main extends App {
    Console.setIn(new FileInputStream("example.in"))

    Console.setIn(new FileInputStream("B-small-practice.in"))
    Console.setOut(new FileOutputStream("B-small-practice.out"))

    Console.setIn(new FileInputStream("B-large-practice.in"))
    Console.setOut(new FileOutputStream("B-large-practice.out"))

    def solve(building:Int, mWay:Long):Option[Array[Array[Int]]] = {
        val maximum = Math.pow(2, building - 2).toLong
        if (maximum < mWay) {
            None
        } else {
            val result: Array[Array[Int]] = (for (row <- 1L until building) yield {
                (for (col <- 0 until building) yield if (row < col) 1 else 0).toArray
            }).toArray

            val header = if (maximum == mWay) {
                0 +: Array.ofDim[Int](building - 1).map(x => 1)
            } else {
                mWay.toBinaryString.toArray.map(_.toInt - '0') :+ 0
            }
            Some((Array.ofDim[Int](building - header.length) ++ header) +: result)
        }
    }

    val cases = StdIn.readLine().toInt
    (1 to cases) foreach { i => {
        val Array(b, m) = StdIn.readLine().split(" ")
        val text = solve(b.toInt, m.toLong) match {
            case Some(array:Array[Array[Int]]) =>
                "POSSIBLE\n" + array.map(_.mkString).mkString("\n")
            case _ =>
                "IMPOSSIBLE"
        }
        println(s"Case #$i: $text")
    }}
}