Swift-组合栈

题目:设计一种数据结构，在前一个栈填满时新建一个栈，push()和pop()与普通栈的操作方法相同.

核心代码:
<pre><code>`class Stacks {

let maxSize:Int = 5

var bufferData:[[Int]] = []

func push(num:Int) {
    
    if bufferData.count == 0 {
        var data:[Int] = []
        data.append(num)
        bufferData.append(data)
    } else {
        var data:[Int]? = bufferData.last
        if (data?.count)! < maxSize {
            data?.append(num)
            bufferData[bufferData.count - 1] = data!
        } else {
            var stack:[Int] = []
            stack.append(num)
            bufferData.append(stack)
        }
        
    }
    
}

func pop() -> Int? {
    
    if bufferData.count == 0 {
        return nil
    }
    
    var data:[Int] = bufferData.last!
    var lastIndex:Int = bufferData.count - 1
    if data.count == 0 {
        if bufferData.count == 1 {
            return nil
        } else {
            bufferData.removeLast()
            lastIndex -= 1
            data = bufferData[lastIndex]
        }
    }
    
    let value:Int = data.last!
    
    data.removeLast()
    
    bufferData[lastIndex] = data

    return value
}

}`</code></pre>

测试代码:
<pre><code>`var stacks:Stacks = Stacks()

for i in 0..<13 {
stacks.push(num: i)
}

print("(stacks.bufferData)")

for i in 0..<8 {
var value:Int? = stacks.pop()
if value != nil {
print("FlyElephant--Pop---(value!)")
}
}
print("(stacks.bufferData)")`</code></pre>