PAT甲级JAVA版 1001 A+B Format（20分）

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(",");
        }
    }
}