最小栈

• 使用切片slice实现

type MinStack struct {
    stack []int
    minIndex int
    length int
}


/** initialize your data structure here. */
func Constructor() MinStack {
    return MinStack{}
}


func (this *MinStack) Push(val int)  {
    this.stack = append(this.stack, val)
    this.minIndex = this.calculateMinIndex()
    this.length++
}


func (this *MinStack) Pop()  {
    this.stack = this.stack[:len(this.stack)-1]
    this.minIndex = this.calculateMinIndex()
    this.length--
}


func (this *MinStack) Top() int {
    return this.stack[this.length-1]
}


func (this *MinStack) GetMin() int {
    return this.stack[this.minIndex]
}

func (this *MinStack)calculateMinIndex()int{
    var min_index = 0
    for i:=1;i<len(this.stack);i++{
        if this.stack[i]<this.stack[min_index]{
            min_index = i
        }
    }
    return min_index
}

• 使用list.List实现（双链表）

type MinStack struct {
	min int
	stack list.List
}


/** initialize your data structure here. */
func Constructor() MinStack {
	return MinStack{min:math.MaxInt64}
}


func (this *MinStack) Push(val int)  {
	if val<this.min{
		this.min = val
	}
	this.stack.PushBack(val)
}


func (this *MinStack) Pop()  { 
    if this.min==this.stack.Back().Value.(int){
        this.stack.Remove(this.stack.Back())
        this.min = math.MaxInt64
        for e:=this.stack.Front();e!=nil;e=e.Next(){
            val := e.Value.(int)
            if val<this.min{
                this.min = val
            }
        }
    }else{
        this.stack.Remove(this.stack.Back())
    }
    
}


func (this *MinStack) Top() int {
	return this.stack.Back().Value.(int)
}


func (this *MinStack) GetMin() int {
	return this.min
}