public class T {
public static void main(String[] args) {
int i=123456789;
Solution s=new Solution();
System.out.println(s.intToroman(1234567890));
System.out.println(s.intToroman(150001));
System.out.println(s.intToroman(30150000));
}
}

class Solution {
String[] metadata=new String[]{"零","一","二","三","四","五","六","七","八","九"};
String[] bit=new String[]{"","十","百","千","","万","亿"};


public String intToroman(int i){
String result="";
int r=0;
while(i>0){
int cur=i%10000;
i=i/10000;
boolean flag=cur<1000&&i>0; //计算前面需要补零的情况
int index=0;
String s="";
while(cur>0){
s= metadata[cur%10]+ (cur%10==0?"":bit[index]) +s;
cur=cur/10;
index++;
}
//每四位,加单位,补零
result=(flag?"零":"")+s+bit[4+r]+result;
r++;
}
//如果有多个位都是零,则保留一个.各位的零抹去
return result.replaceAll("零+","零").replaceAll("零$","");
}
}
结果:
一十二亿三千四百五十六万七千八百九十
一十五万零一
三千零一十五万