155.最小栈.go

/*
 * @lc app=leetcode.cn id=155 lang=golang
 *
 * [155] 最小栈
 */

// @lc code=start
type MinStack struct {
	stack []int
	min   []int
}


/** initialize your data structure here. */
func Constructor() MinStack {
	return MinStack{
		stack: make([]int, 0),
		min:   make([]int, 0),
	}
}


func (this *MinStack) Push(x int)  {
	if x < this.GetMin() {
		this.min = append(this.min, x)
	} else {
		this.min = append(this.min, this.GetMin())
	}
	this.stack = append(this.stack, x)
}


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


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


func (this *MinStack) GetMin() int {
	if len(this.stack) == 0 {
		return 1 << 31
	}
	return this.min[len(this.stack)-1]
}


/**
 * Your MinStack object will be instantiated and called as such:
 * obj := Constructor();
 * obj.Push(x);
 * obj.Pop();
 * param_3 := obj.Top();
 * param_4 := obj.GetMin();
 */
// @lc code=end