fun main(arr:Array<String>) {
    val inputCount = readLine()!!.toInt()
    val ans = (1..inputCount).map { getValue(readLine()!!) }.min()!!
    println(ans)
}

fun getValue(num:String):Long {
    val max = charToInt(num.max()!!) + 1L
    var base = 1L
    var total = 0L
    for(c in num.reversed()) {
        total += base * charToInt(c)
        base *= max
    }
    return total
}

fun charToInt(c:Char):Int {
    if(c <= '9') {
        return c.toString().toInt();
    }
    return (c - 'A') + 10;
}