方法一:
class Solution
{
public:
vector<int>plusOne(vector<int> &num)
{
int n = num.size();
//若数位为9,则置0;否则加一返回该数
for (int i = n - 1;i >= 0;--i)
{
if (num[i] == 9)
num[i] = 0;
else
{
num[i] += 1;
return num;
}
}
//若最高位为0,则加一返回
if (num.front() == 0)
num.insert(num.begin(), 1);
return num;
}
};