LeetCode Plus One

class Solution {
public:
    vector<int> plusOne(vector<int> &digits) {
        // Start typing your C/C++ solution below
        // DO NOT write int main() function
        int  c=0;
        int i=digits.size()-1;
        vector<int> v;
        int t=digits[i];
        digits[i]=(t+1)%10;
        c=(t+1)/10;
        
        for(i--;i>=0;i--)
        {
            t=digits[i];
            digits[i]=(c+t)%10;
            c=(t+c)/10;        
        }
        if(c)
            v.push_back(c);
        for(i=0;i<digits.size();i++)
            v.push_back(digits[i]);
        
        return v;
    }
};



class Solution {
public:
    vector<int> plusOne(vector<int> &digits) {
        // Start typing your C/C++ solution below
        // DO NOT write int main() function
        int  c=1;   
        int i;
        for(i=digits.size()-1;i>=0;i--)
        {
            int t=digits[i];
            digits[i]=(c+t)%10;
            c=(t+c)/10;        
        }
        if(c)
            digits.insert(digits.begin(),c);
        return digits;
    }
};


class Solution {
public:
    vector<int> plusOne(vector<int> &digits) {
        // Start typing your C/C++ solution below
        // DO NOT write int main() function
        vector<int> v(digits);
        int  c=1;   
        int i;
        
        for(i=v.size()-1;i>=0;i--)
        {
            int t=v[i];
            v[i]=(c+t)%10;
            c=(t+c)/10;        
        }
        if(c)
            v.insert(v.begin(),c);
        return v;
    }
};