import java.io.PrintWriter import java.util.* import kotlin.math.* fun PrintWriter.solve() { val n = nextInt() val a = Array(n) { nextInt() } var ans = 0L for (i in 0 until n) { for (j in i + 1 until n) { ans += (a[i] % a[j] - a[j] % a[i]).absoluteValue } } println(ans) } fun main() { val writer = PrintWriter(System.out, false) writer.solve() writer.flush() } // region Scanner private var st = StringTokenizer("") private val br = System.`in`.bufferedReader() fun next(): String { while (!st.hasMoreTokens()) st = StringTokenizer(br.readLine()) return st.nextToken() } fun nextInt() = next().toInt() fun nextLong() = next().toLong() fun nextLine() = br.readLine() fun nextDouble() = next().toDouble() // endregion