50道编程题之08:求s=a+aa+aaa+aaaa+aaaa...a的值，其中a是一个数字。几个数相加有键盘控制

package com.demo;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Scanner;

/**
 * Created by 莫文龙 on 2018/3/27.
 */

//求 s=a+aa+aaa+aaaa+aaaa...a的值，其中a是一个数字。几个数相加有键盘控制

public class Demo8 {

    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        System.out.print("请输入a的值:");
        String a = br.readLine();
        System.out.println("请输入a的个数:");
        String count = br.readLine();
        String aa = a;
        int sum = 0;
        for (int i = 1; i <= Integer.parseInt(count) ; i ++) {
            int b = Integer.parseInt(a);
            sum += b;
            a += aa;
        }
        System.out.println(sum);
    }

}