1001 A+B Format （20 分）
Calculate a+b and output the sum in standard format -- that is, the digits must be separated into groups of three by commas (unless there are less than four digits).
Input Specification:
Each input file contains one test case. Each case contains a pair of integers a and b where.The numbers are separated by a space.
Output Specification:
For each test case, you should output the sum of a and b in one line. The sum must be written in the standard format.
Sample Input:
-1000000 9
Sample Output:
-999,991
1001 A+B格式化（20分）
计算A+B的结果并且以标准格式输出——即，输出的结果必须每三个数字用逗号分隔为一组（除非结果不足四个数字）。
输入规格：
每个输入文件包含一个测试用例。每个用例都包含一对整数a和b，其中。数字用空格分隔。
输出规格：
对于每个测试用例，您应该在一行中输出a和b的总和。总和必须用标准格式写。
输入样例：
-1000000 9
输出样例：
-999,991
代码：
import java.util.Scanner;
public class Main {
private static Scanner sc;
public static void main(String[] args) {
// TODO Auto-generated method stub
int a;
int b;
String sum;
sc = new Scanner(System.in);
a = sc.nextInt();
b = sc.nextInt();
sc.close();
sum = a + b + "";
for (int i = 0; i < sum.length(); i++) {
System.out.print(sum.substring(i, i + 1));
if ("-".equals(sum.substring(i, i + 1)))
continue;
if ((i + 1) % 3 == sum.length() % 3 && i != sum.length() - 1)
System.out.print(",");
}
}
}
