解题4（NumberToEnglish ）

题目描述

Jessi初学英语，为了快速读出一串数字，编写程序将数字转换成英文：

如22：twenty two，123：one hundred and twenty three。

 

说明：

数字为正整数，长度不超过九位，不考虑小数，转化结果为英文小写；

输出格式为twenty two；

非法数据请返回“error”；

关键字提示：and，billion，million，thousand，hundred。

 

方法原型：public static String parse(long num) 

 

 

 

输入描述:

输入一个long型整数

输出描述:

输出相应的英文写法

示例1

输入

2356

输出

two thousand three hundred and fifty six

代码如下：

package com.yzh.hehe;

import java.util.Scanner;

public class NumberToEnglish {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Scanner scanner=new Scanner(System.in);
        while (scanner.hasNext()) {
            long num=scanner.nextLong();
            System.out.println(parse(num));
        }
        scanner.close();
    }
    
    public static String parse(long num){
        String[] geweiArr={"one","two","three","four","five","six","seven","eight","nine" };
        String[] shiweiArr={"twenty","thirty","forty","fifty","sixty","seventy","eighty","ninety"};
        String[] shiduoArr={"ten","eleven","twelve","thirteen","fourteen","fifteen","sixteen","seventeen","eighteen","nineteen"};
        String numString=String.valueOf(num);
//        要求最多不超过九位数，不够九位的前面填0
        for (int i = numString.length(); i <9; i++) {
            numString="0"+numString;            
        }
        StringBuilder stringBuilder=new StringBuilder();
        String million=numString.substring(0,3);//以1000（thousand）每三位为一个部分（个十百）来处理
        int miBaiInt=Integer.parseInt(million.substring(0, 1));
        boolean  flag=false;//判断是否加and的标志
        //处理三位组成的数当中的百位
        if (miBaiInt!=0) {
            flag=true;
            stringBuilder.append(geweiArr[miBaiInt-1]+" hundred");
        }
        int miShiInt=Integer.parseInt(million.substring(1,2));//三位组成的数当中的十位
        int migeInt=Integer.parseInt(million.substring(2));//三位组成的数当中的个位
        if ((miShiInt!=0||migeInt!=0)&&flag) {
            stringBuilder.append(" and ");
        }
        //十位为1时十位和个位可同时处理，否则，先处理十位，在处理个位
        if (miShiInt==1) {
            int temp=Integer.parseInt(million.substring(1));//十位个位同事处理
            stringBuilder.append(shiduoArr[temp-10]);
        } 
        //十位，个位分别处理
        else {
             flag=false;
            if(miShiInt!=0){
                flag=true;
                stringBuilder.append(shiweiArr[miShiInt-2]);
            }
            if (flag&&migeInt!=0) {
                stringBuilder.append(" "+geweiArr[migeInt-1]);
            }else if(migeInt!=0){
                stringBuilder.append(geweiArr[migeInt-1]);
            }
            
        }
        int length=stringBuilder.length();//判断是否存在million和thousand
        if (length!=0) {
            stringBuilder.append(" million ");
        }
        String thousand=numString.substring(3,6);//处理第二个三位组成的部分
        int thBaiInt=Integer.parseInt(thousand.substring(0,1));
        flag=false;
        if (thBaiInt!=0) {
            flag=true;
            stringBuilder.append(geweiArr[thBaiInt-1]+" hundred");
        }
        int thShiInt=Integer.parseInt(thousand.substring(1,2));
        int thGeInt=Integer.parseInt(thousand.substring(2));
        if (flag&&(thShiInt!=0||thGeInt!=0)) {
            stringBuilder.append(" and ");
        }
        if (thShiInt==1) {
            int temp=Integer.parseInt(thousand.substring(1));
            stringBuilder.append(shiduoArr[temp-10]);
        }else {
            flag=false;
            if (thShiInt!=0) {
                flag=true;
                stringBuilder.append(shiweiArr[thShiInt-2]);
            }
            
            if (flag&&thGeInt!=0) {
                stringBuilder.append(" "+geweiArr[thGeInt-1]);
            }else if (thGeInt!=0) {
                stringBuilder.append(geweiArr[thGeInt-1]);
            }
        }
        
        if (stringBuilder.length()>length) {
            stringBuilder.append(" thousand ");
        }
        String bsg=numString.substring(6);//处理第三个三位组成的部分
        int bsgBaiInt=Integer.parseInt(bsg.substring(0,1));
        flag=false;
        if (bsgBaiInt!=0) {
            flag=true;
            stringBuilder.append(geweiArr[bsgBaiInt-1]+" hundred");
        }
        int bsgShiInt=Integer.parseInt(bsg.substring(1,2));
        int bsgGeInt=Integer.parseInt(bsg.substring(2));
        if (flag&&(bsgShiInt!=0||bsgGeInt!=0)) {
            stringBuilder.append(" and ");
            
        }
        if (bsgShiInt==1) {
            int temp=Integer.parseInt(bsg.substring(1));
            stringBuilder.append(shiduoArr[temp-10]);
        }else {
            flag=false;
            if (bsgShiInt!=0) {
                flag=true;
                stringBuilder.append(shiweiArr[bsgShiInt-2]);
            }
            if (flag&&(bsgGeInt!=0)) {
                stringBuilder.append(" "+geweiArr[bsgGeInt-1]);
            }else if (bsgGeInt!=0) {
                stringBuilder.append(geweiArr[bsgGeInt-1]);
            }
        }
        return stringBuilder.toString();
                
    }

}