ruoguluo

public class FindDuplicate {

    public static void main(String[] args) {
        FindDuplicate fd = new FindDuplicate();
        int[] nums = new int[]{1, 2, 3, 4, 5, 6, 1};
        assert (fd.find(nums) == 1);
        nums = new int[]{1, 2, 3, 4, 5, 6, 1};
        assert (fd.find(nums) == 1);
        nums = new int[]{2, 2, 3, 4, 5, 6, 1};
        assert (fd.find(nums) == 2);