Plus One Solutions in C++

// Source : https://oj.leetcode.com/problems/plus-one/
// Author : Hao Chen
// Date   : 2014-06-21



#include <iostream>
#include <vector>
using namespace std;

vector<int> plusOne(vector<int> &digits) {
    int carry=1;
    vector <int> v;
    while(digits.size()>0){
        int x = digits.back();
        digits.pop_back();
        x = x + carry;
        v.insert(v.begin(), x%10);
        carry = x/10;
    }
    if (carry>0){
        v.insert(v.begin(), carry);
    }
    return v;

}

void printVector(vector<int>& v)
{
    cout << "{ ";
    for(int i=0; i<v.size(); i++){
        cout << v[i] << " ";
    }
    cout << "} " << endl;
}


int main()
{
    int a[]={9,9,9};
    vector<int> d(&a[0], &a[0]+sizeof(a)/sizeof(int));
    vector<int> v = plusOne(d);
    printVector(v);
    return 0;
}

#include <vector>
using std::vector; 

class Solution {
public:
    vector<int> plusOne(vector<int> &digits) {
        for (auto iter = digits.rbegin(); iter != digits.rend(); ++iter)
            if (++*iter < 10) break;
            else *iter = 0; 
        if (digits.front() == 0) digits.insert(digits.begin(), 1);
        return digits;
    }
};

/// Source : https://leetcode.com/problems/plus-one/description/
/// Author : liuyubobobo
/// Time   : 2018-06-03

#include <iostream>
#include <vector>

using namespace std;

/// Ad Hoc
/// Time Complexity: O(n)
/// Space Complexity: O(1)
class Solution {
public:
    vector<int> plusOne(vector<int>& digits) {

        digits[digits.size() - 1] ++;
        for(int i = digits.size() - 1 ; i >= 1 ; i --)
            if(digits[i] == 10){
                digits[i] = 0;
                digits[i - 1] ++;
            }

        if(digits[0] == 10){
            digits[0] = 0;
            digits.insert(digits.begin(), 1);
        }

        return digits;
    }
};


int main() {

    return 0;
}