怎样求出22/7小数点后的100位数？该如何解决

  public static void main(String[] args) {    BigDecimal a = new BigDecimal(22);    a = a.divide(new BigDecimal(7), 100,BigDecimal.ROUND_HALF_UP);    System.out.println(a);  }
------解决方案--------------------
Java code
public class Test {    public static void main(String[] args) {        System.out.println(div7(22, 100));  // 22/7 的第 100 位        System.out.println(div7(33, 100));  // 33/7 的第 100 位    }    public static int div7(int numerator, int digit) {                  int mod = numerator % 7;        if(mod == 0) {            return 0;        }        String repetend = "142857";        int[] shift = {0, 2, 1, 4, 5, 3};        char c = repetend.charAt((digit + shift[mod - 1] - 1) % 6);        return c - '0';    }}