LeetCode 232. 用栈实现队列

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题目描述
思路分析
参考代码
相似题目

题目描述

🔥 232. 用栈实现队列

思路分析

思路描述

参考代码

type MyQueue struct {
	inStack  []int
	outStack []int
}

func Constructor() MyQueue {
	return MyQueue{}
}

func (q *MyQueue) Push(x int) {
	q.inStack = append(q.inStack, x)
}

func (q *MyQueue) Pop() int {
	val := q.Peek()
	q.outStack = q.outStack[:len(q.outStack)-1]
	return val
}

func (q *MyQueue) Peek() int {
	if len(q.outStack) == 0 {
		for len(q.inStack) > 0 {
			q.outStack = append(q.outStack, q.inStack[len(q.inStack)-1])
			q.inStack = q.inStack[:len(q.inStack)-1]
		}
	}
	return q.outStack[len(q.outStack)-1]
}

func (q *MyQueue) Empty() bool {
	return len(q.inStack) == 0 && len(q.outStack) == 0
}

🍏 点击查看 Java 题解

class MyQueue {
    private Stack<Integer> stack1;
    private Stack<Integer> stack2;

    public MyQueue() {
        stack1 = new Stack<>();
        stack2 = new Stack<>();
    }

    public void push(int x) {
        stack1.push(x);
    }

    public int pop() {
        peek();
        return stack2.pop();
    }

    public int peek() {
        if (stack2.isEmpty()) {
            while (!stack1.isEmpty()) {
                stack2.push(stack1.pop());
            }
        }
        return stack2.peek();
    }

    public boolean empty() {
        return stack1.isEmpty() && stack2.isEmpty();
    }
}

相似题目

题目	难度	题解
用队列实现栈	Easy

本文作者: HGNULB

本文链接: https://hgnulb.github.io/blog/06263683