Note:

The use of Vector:1.initializeint x[10]={9,8,7,6,5,4,3,2,1,0};vector test(x,x+10);

2.end();begin();vector.begin() points to the first item,while vector.end() doesn't point to the last item but after it.

3.vector.insert(pointer which indicates the location to insert,the item)

class Solution {public:    /**     * @param digits a number rePResented as an array of digits     * @return the result     */    vector<int> plusOne(vector<int>& digits) {        // Write your code here        vector<int>::iterator p1;        p1=digits.end()-1;        while(*p1==9){            *p1=0;            p1--;        }        if(p1!=digits.begin()-1)            (*p1)++;        else            digits.insert(digits.begin(),1);        return digits;    }};