import java.lang.StringBuilder
import java.util.*
import kotlin.collections.ArrayList
import kotlin.math.*

fun main(args:Array<String>) {
    /*
    val t = readLine()!!.toInt()
    repeat(t) {
        solve()
    }
    */
    solve()
}

fun solve() {
    val (n, a, b) = readLine()!!.split(" ").map{it.toLong()}.toLongArray()
    val ans = min((n - 1) * a - b * n, -(n - 1) * a - if (n % 2 == 0L) 0 else b)
    println(ans)
}