I got a curious about how compiler determines a value's **rawValue**. First, I give you an example code:

    enum Rank: Int{
        case Tom
        case Jane
        case Steve, Tim
    }

In this situation, `Rank.Tom.rawValue` is 0, also `Rank.Jane.rawValue` is equal to 1 (increment as 1). It means, compiler determines **rawValue** automatically starting from 0, **if data type is Int.**

Let me give you an another example, I decided another starting **rawValue** point as 5 like below:

    enum Rank: Int{
        case Tom = 5
        case Jane
        case Steve, Tim
    }

Then `Rank.Jane.rawValue` is equal to 6.  Also, If I set Jane's **rawValue** as 10 (keeping Tom = 5), `Rank.Steve.rawValue` is equal to 11.