Two stacks to implement a queue

The topic is very simple, today looked at the Java generic type of things, with the generic rewrite a bit:

Package Com.wy.oj;import java.util.stack;/** * Created by WY on 2016/12/23 023. */public class Twostackqueue<t> {private stack<t> S1 = new stack<> ();//Queue Private Stack<t&gt ; S2 = new stack<> ();        Out of public T pop () {if (IsEmpty ()) return null;        if (!s2.isempty ()) return S2.pop ();            else {while (!s1.isempty ()) S2.push (S1.pop ());        return S2.pop ();    }} public void push (T item) {S1.push (item);    } public int size () {return s1.size () + s2.size ();    } public boolean IsEmpty () {return (S1.isempty () && s2.isempty ()); }//test public static void main (string[] args) {twostackqueue<string> qs = new Twostackqueue<> ()        ;        For (String s: "Qing li si nian chun". Split ("")) Qs.push (s);        for (int i=0; i<3; ++i) System.out.println (Qs.pop ());        System.out.println (); For (String s: "tEn Zi Jing ". Split (")) Qs.push (s);        while (!qs.isempty ()) System.out.println (Qs.pop ());        Twostackqueue<integer> qi = new twostackqueue<> ();        for (int i=10; i<100; i=2*i) Qi.push (i);    while (!qi.isempty ()) System.out.println (Qi.pop ()); }}

　　

Two stacks to implement a queue