求Sn=2+22+222+2222+22222+22...2222(最后一项n个2）java

以下是使用Java编写的求Sn的程序：

import java.util.Scanner;

public class SnCalculator {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.println("请输入a和n的值：");
        int a = scanner.nextInt();
        int n = scanner.nextInt();
        int m = 0;
        int s = 0;
        for (int i = 1; i <= n; i++) {
            m = m + a;
            s = s + m;
            m = 10 * m;
        }
        System.out.printf("a+aa+aaa+...=%d\n", s);
    }
}