import java.util.Scanner

fun main(args: Array<String>) {
    val scanner = Scanner(System.`in`)
    val n = scanner.nextInt()
    val a = Array<Int>(101, { 0 })
    for (i in 1..n) {
        var d = scanner.nextInt()
        a[d] = 1
    }
    val answer = a.reduce { n1, n2 -> n1 + n2 }
    println(answer)
}