《剑指offer》-用两个栈实现队列

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题目：用两个栈实现一个队列，完成在队尾插入结点和在队头删除结点的功能。
实在不知道该怎么写。。。。。。只能按照书上给的代码改成java版本的了，哈哈哈……机智如我

import java.util.Stack;public class CQueue {    public static Stack<Integer> stack1 = new Stack<Integer>();    public static Stack<Integer> stack2 = new Stack<Integer>();    public static void main(String[] args) {        // TODO Auto-generated method stub        CQueue c = new CQueue();        for(int i = 0; i < 5; i++){            c.appendTail(i);            c.printQueue();        }        for(int i = 0; i < 3; i++){            c.deleteHead();            c.printQueue();        }    }    public void printQueue(){//打印的是出队的顺序        Stack<Integer> tmp = new Stack<>();        while(!stack2.empty()){            tmp.push(stack2.pop());            System.out.print(tmp.peek() + " ");        }        while(!tmp.empty()){            stack2.push(tmp.pop());        }        while(!stack1.empty()){            tmp.push(stack1.pop());        }        while(!tmp.empty()){            stack1.push(tmp.pop());            System.out.print(stack1.peek() + " ");        }        System.out.println();    }    public void appendTail(Integer i){        stack1.push(i);    }    public int deleteHead(){        if(stack2.empty()){            while(!stack1.empty()){                Integer tmp = stack1.pop();                stack2.push(tmp);            }        }        if(stack2.empty()){            System.out.println("queue is empty");        }        Integer i = stack2.pop();        return i;    }}

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