172. 删除元素

 1 int removeElement(vector<int> &A, int elem) {
 2         // write your code here
 3         vector<int>::iterator it=A.begin();
 4         while(it!=A.end()){
 5             if(*it==elem){
 6                 it=A.erase(it);
 7             }
 8             else{
 9                 it++;
10             }
11         }
12         return A.size();
13     }

int removeElement(vector<int> &A, int elem) {
        // write your code here
        int num=0;
        for (int i = 0; i<A.size(); i++) {  
            if (A[i] != elem) {  
                A[num++] = A[i];  
            }  
        }  
        return num;
}