计蒜客013-整数换成罗马数字

给定一个整数num，( 1<=num<=3999)，将整数转换成罗马数字。

如1,2,3,4,5对应的罗马数字分别位I，II，III，IV，V等。

格式：

   第一行输入一个整数，接下来输出对应的罗马数字。

提示：

   罗马数字的常识见此链接，对做题有帮助哦～尤其是表示方法。

http://baike.baidu.com/link?url=injU8M4bAoc2zRZQ1GtgrfvuzCJO9PLnq6fpQGJLenakbzo-rS8p-qsYHR_81-aN
           

样例输入

123      

样例输出

CXXIII      

import java.util.Scanner;

public class Main {  
    public static void main(String[] args) {
    	Scanner in = new Scanner(System.in);
    	
    	String roman[][]={{"","I","II","III","IV","V","VI","VII","VIII","IX"},
            {"","X","XX","XXX","XL","L","LX","LXX","LXXX","XC"},
            {"","C","CC","CCC","CD","D","DC","DCC","DCCC","CM"},
            {"","M","MM","MMM"}};
    	int i,j,n;
    	int num = in.nextInt();
    	for(j=0,i=10000;j<4;++j,i/=10)
    	{
    		n=(num%i)/(i/10);
    		System.out.print(roman[3-j][n]);
    	}
    }
}