013-题目：求s=a+aa+aaa+aaaa+aa...a的值，其中a是一个数字。

import java.util.Scanner;

public class Main {

	public static int getSum(int a,int n) {
		int i = 0;
		int num = 0;
		while (i<n) {
			num +=a*Math.pow(10, i);
			i++;
		}
		return num;
	}
	
	@SuppressWarnings("resource")
	public static void main(String[] args) {
		Scanner in = new Scanner(System.in);
		int a = in.nextInt();
		int n = in.nextInt();
		int sum = 0;
		for (int i = 1; i <= n; i++) {
			sum +=getSum(a, i);
		}
		System.out.println(sum);
	}
}

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