得到彼此位数上的数字不相同的三位数的所有组合,该如何处理

public class Test {    public static void find() {        int num = 102,count = 0;        int a,b,c;//百，十，个        while(num <= 987){            a = num / 100;            b = (num - a * 100) / 10;            c = num % 10;            if(a != b && a != c && b != c){                System.out.println(num);                ++count;            }            ++num;        }        System.out.println("count = " + count);    }    public static void main(String[] args) {        find();    }}