把数组排成最小的数

直接用暴力法列出所有排列然后选最小没想到能过。

public String PrintMinNumber(int [] numbers) {
        if(numbers==null||numbers.length==0)return "";
        long min = Long.MAX_VALUE;
        ArrayList<String> help = help(numbers, 0);
        for (String s : help) {
            long i = Long.valueOf(s);
            if(i<min) min =i;
        }
        return String.valueOf(min);
    }

    private ArrayList<String> help(int[] nums, int i) {
        ArrayList<String> res = new ArrayList<>();
        if(i==nums.length-1){
            res.add(String.valueOf(nums[i]));
            return res;
        }

        for (int j = i++; j <nums.length ; j++) {
            int temp = nums[j];
            nums[j]=nums[i-1];
            nums[i-1]=temp;
            ArrayList<String> newRes = help(nums, i);
            //处理结果
            for (int k = 0; k < newRes.size(); k++) {
                res.add(String.valueOf(nums[i-1])+newRes.get(k));
            }

            temp = nums[j];
            nums[j]=nums[i-1];
            nums[i-1]=temp;
        }
        return res;
    }