Leetcode-plus One

#include <iostream>
#include <cstdio>
#include <vector>
#include <string>

using namespace std;
class Solution
{
	public:
		vector<int> plusOne(vector<int> &digits)
		{
			vector<int> ans;
			//从尾部开始扫描，发现9
			int i = digits.size() - 1;
			while(i >= 0 && digits[i] == 9)
				i--;
			if(i < 0)	//9999的情况需要增加一位，置首位为1,即10000
				ans.push_back(1);
			else	//其他情况，直接在最后一位加1即可
			{
				for(int j = 0; j < i; j++)
					ans.push_back(digits[j]);
				ans.push_back(digits[i] + 1);
			}

			for(int j = 1; j < digits.size() - i; j++)
				ans.push_back(0);//逢9进1,后面补0
			return ans;
		}
};

int main()
{
		Solution *a = new Solution();
		vector<int> digits;
		int time, num;
		cin>>time;
		while(time--)
		{
			cin>>num;
			digits.push_back(num);
		}
		vector<int> ans;
		ans = a->plusOne(digits);
		vector<int> plusOne(digits);
		int i = 0;
		while(i != ans.size())
		{
			cout<<ans[i]<<" ";
			i++;
		}
		cout<<endl;
		return 0;

}