UVA - 11821 - High-Precision Number

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.math.BigDecimal;

public class Main {

    public static void main(String[] args) throws IOException {
        InputStreamReader isr = new InputStreamReader(System.in);
        BufferedReader br = new BufferedReader(isr);
        StringBuffer sb = new StringBuffer("");
        String m = "";
        int num = Integer.parseInt(br.readLine());
        for (int i = 0; i < num; i++) {
            BigDecimal bd = BigDecimal.ZERO;
            while (true) {
                BigDecimal bd2 = new BigDecimal(br.readLine());
                if (bd2.compareTo(BigDecimal.ZERO) == 0) {
                    break;
                }
                bd = bd.add(bd2);
            }
            sb.append(trail(bd)).append("\n");
        }
        System.out.print(sb);
    }
   
    static String trail(BigDecimal bd){
        String ans = bd.toString();
            if (ans.indexOf('.') != -1) {
                int lenOfSubString = ans.length() - 1;
                while (ans.charAt(lenOfSubString) == '0') {
                    lenOfSubString--;
                }
                if (ans.charAt(lenOfSubString) == '.') {
                    ans = ans.substring(0, lenOfSubString);
                } else {
                    ans = ans.substring(0, lenOfSubString + 1);
                }
            }
            return ans;
    }
}