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题目描述

https://leetcode-cn.com/problems/min-stack/

解

type MinStack struct {
    Min    []int
    Normal []int
}


/** initialize your data structure here. */
func Constructor() MinStack {
    var r MinStack
    return r
}
func (this *MinStack) Push(x int) {
    this.Normal = append(this.Normal, x)
    if len(this.Min) > 0 {
        if this.Min[len(this.Min)-1] >= x {
            this.Min = append(this.Min, x)
        }
    } else {
        this.Min = append(this.Min, x)
    }
}

func (this *MinStack) Pop() {
    if len(this.Normal) > 0 {
        if this.Min[len(this.Min)-1] == this.Normal[len(this.Normal)-1] {
            this.Min = this.Min[:len(this.Min)-1]
        }
        this.Normal = this.Normal[:len(this.Normal)-1]
    }
}

func (this *MinStack) Top() int {
    if len(this.Normal) > 0 {
        return this.Normal[len(this.Normal)-1]
    }
    return 0
}

func (this *MinStack) GetMin() int {
    if len(this.Min) > 0 {
        return this.Min[len(this.Min)-1]
    }
    return 0
}

/**
 * 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();
 */

思路

用一个辅助就很简单了！