把数组排成最小的数

//方法一：定义lamda函数进行比较操作，比较容易理解
string PrintMinNumber(vector<int> numbers)
{
	sort(numbers.begin(), numbers.end(), [](const int& a, const int& b){
		return to_string(a) + to_string(b) < to_string(b) + to_string(a); });
	string res;
	for (auto c : numbers)
		res += to_string(c);
	return res;
}
    
//方法二：使用全排列的方法
void getMinCombineNumberInArray(vector<int> &numbers, int begin, long long& minValue){
	if (numbers.size() - 1 == begin){
		string str = "";
		for (int i = 0; i < numbers.size();i++)
		{
			string temp = to_string(numbers[i]);
			str += temp;
		}

		long long value = stol(str);
		if (minValue > value)
			minValue = value;
	}

	for (int i = begin; i < numbers.size(); i++)
	{
		swap(numbers[i], numbers[begin]);
		getMinCombineNumberInArray(numbers, begin + 1, minValue);
		swap(numbers[i], numbers[begin]);
	}
}
//全排列
string PrintMinNumber2(vector<int> numbers){
	string res;
	if (numbers.empty())
		return res;
	long long minValue = LLONG_MAX;
	getMinCombineNumberInArray(numbers, 0, minValue);
	
	res = to_string(minValue);
	return res;
}