遞迴實現一小演算法

/** * Implement algorithm like:f(2,3)=2+22+222;f(3,4)=3+33+333+3333...... */public class Test{    // get each one value    public static int recur(int a ,int b){        if (b == 1) {            return a;        }else{            return a * (int) Math.pow(10, b - 1) + recur(a, b - 1);        }    }    // get the summary of each one value    public static int getValue(int a, int b) {        int sum = 0;        for (int i = 1; i <= b; i++) {            System.out.print(recur(a, i) + "+");            sum = sum + recur(a, i);        }        return sum;    }    public static void main(String[] args) {        System.out.println("recursive result: " + recur(2, 3));        Test.getValue(2, 3);    }}