gCube.scala

import java.io.PrintWriter

object Codejam {

	// Config.
	val inputFilePath = "B-large-practice.in"
	val outputFilePath = "B-large-practice.out"
	val isConsole = false

	// Main procedure.
	def main(args: Array[String]): Unit = {
		val inputLines = scala.io.Source.fromFile(inputFilePath).getLines()
		val inputCount = inputLines.next.toInt
		val writer = if (isConsole) new PrintWriter(scala.Console.out)
		else new PrintWriter(outputFilePath)

		try {
			process(inputCount, inputLines)(writer.println)
		} finally {
			writer.flush()
			writer.close()
		}
	}

	// Process input value.
	def process(inputCount: Int, inputLines: Iterator[String])(lineOut: String => Unit) = {
		for (num <- 1 to inputCount) {
			val Array(n, m) = inputLines.next().split(" ").map(_.toInt)
			val as = inputLines.next().split(" ").map(_.toInt)

			lineOut(s"Case #$num:")
			for (i <- 0 until m){
				val Array(l,r) = inputLines.next().split(" ").map(_.toInt)
				val logVol = as.slice(l,r + 1).map(Math.log(_)).sum
				val edge = Math.exp(logVol.toDouble / (r - l + 1).toDouble)
				lineOut(f"${edge}%.9f")
			}
		}
	}

}