代码随想录day9|232用栈实现队列225用队列实现栈|01笔记

232用栈实现队列

逻辑与注意事项

解题代码

    type MyQueue struct {
        stackIn  []int //输入栈
        stackOut []int //输出栈
    }
    
    func Constructor() MyQueue {
        return MyQueue{
            stackIn:  make([]int, 0),
            stackOut: make([]int, 0),
        }
    }
    
    // 往输入栈做push
    func (this *MyQueue) Push(x int) {
        this.stackIn = append(this.stackIn, x)
    }
    
    // 在输出栈做pop，pop时如果输出栈数据为空，需要将输入栈全部数据导入，如果非空，则可直接使用
    func (this *MyQueue) Pop() int {
        inLen, outLen := len(this.stackIn), len(this.stackOut)
        if outLen == 0 {
            if inLen == 0 {
                return -1
            }
            for i := inLen - 1; i >= 0; i-- {
                this.stackOut = append(this.stackOut, this.stackIn[i])
            }
            this.stackIn = []int{}      //导出后清空
            outLen = len(this.stackOut) //更新长度值
        }
        val := this.stackOut[outLen-1]
        this.stackOut = this.stackOut[:outLen-1]
        return val
    }
    
    func (this *MyQueue) Peek() int {
        val := this.Pop()
        if val == -1 {
            return -1
        }
        this.stackOut = append(this.stackOut, val)
        return val
    }
    
    func (this *MyQueue) Empty() bool {
        return len(this.stackIn) == 0 && len(this.stackOut) == 0
    }

225用队列实现栈

第一印象

解题代码

    type MyStack struct {
        queIn []int
        queOut []int
    }
    
    
    func Constructor() MyStack {
        return MyStack{
            queIn: []int{},
            queOut: []int{},
        }
    }
    
    
    func (this *MyStack) Push(x int)  {
        this.queIn = append(this.queIn, x)
    }
    
    
    func (this *MyStack) Pop() int {
        lenIn, lenOut := len(this.queIn), len(this.queOut)
        if lenIn==0 {
            if lenOut == 0 {
                return -1
            }
            for j:=0;j<lenOut;j++ {
                this.queIn = append(this.queIn, this.queOut[j])
            }
            lenIn = lenOut
            this.queOut = make([]int, 0)
            lenOut = 0
        }
        for i:=0;i<lenIn-1;i++ {
            this.queOut = append(this.queOut,this.queIn[i])
        }
        this.queIn = this.queIn[lenIn-1:]
        p := this.queIn[0]
        this.queIn = make([]int, 0)
    
        return p
    }
    
    
    func (this *MyStack) Top() int {
        p := this.Pop()
        this.Push(p)
        return p
    }
    
    
    func (this *MyStack) Empty() bool {
        return len(this.queIn) == 0 && len(this.queOut)==0
    }
    
    
    /**
     * Your MyStack object will be instantiated and called as such:
     * obj := Constructor();
     * obj.Push(x);
     * param_2 := obj.Pop();
     * param_3 := obj.Top();
     * param_4 := obj.Empty();
     */