Calendar.scala

package Main

import java.io.{FileOutputStream, FileInputStream}

import scala.io.StdIn

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

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

    def lcm(a:Long, b:Long) = a * b / gcd(a, b)
    def gcd(a:Long, b:Long):Long = if (0 == b) a else gcd(b, a % b)

    def solve(month:Long, nOfMonth:Long, nOfWeek:Long): Long = {
        val remains = nOfMonth % nOfWeek
        if (0 == remains) {
            month * (nOfMonth / nOfWeek)
        } else {
            val nOfLeapMonth = lcm(remains, nOfWeek)
            val additional = if (0 == (remains * month % nOfLeapMonth)) 1 else 0
            val totalWeek = (month * nOfMonth + nOfWeek - 1) / nOfWeek
            totalWeek + (month - 1) - (remains * month / nOfLeapMonth) + additional
        }
    }

    val cases = StdIn.readLine().toInt
    (1 to cases) foreach { num =>
        val Array(month, nOfMonth, nOfWeek) = StdIn.readLine().split(" ").map(_.toLong)
        println(s"Case #$num: ${solve(month, nOfMonth, nOfWeek)}")
    }
}