swift 变长参数

func getMean(value:Double ...) -> Double {
    var all:Double = 0
    // 把变长参数当数组使用
    for num in value {
        all += num
    }
    return all / Double(value.count)
}

getMean(1,2,3,4,5,6,54)
getMean(1,6)
getMean(1,54)