s = a + aa + aaa+ ...

package Test_1;
import java.util.*;

public class Test_8_1 {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		System.out.print("請輸入a的值和a的行數：");
		Scanner input = new Scanner(System.in);
		int num1 = input.nextInt();
		int num2 = input.nextInt();
		String str = "";
		long s = 0;
		for(int i=1;i<=num2;i++){
			str = str + num1;
			int temp = Integer.parseInt(str);
			s = s + temp;
		}
		System.out.print("最後的結果爲："+s);
		
	}

}