C++自定义函数生成不重复的随机数

vector<int> getRandom(int total)
{
    srand((int)time(NULL));
    std::vector<int> input = *new std::vector<int>();
    for (int i = 0; i < total; i++) {
        input.push_back(i);
    }
    vector<int> output = *new vector<int>();
     
    int end = total;
    for (int i = 0; i < total; i++) {
        vector<int>::iterator iter = input.begin();
        int num = random()%end;
        iter = iter+num;
        output.push_back(*iter);
        input.erase(iter);
        end--;
    }
     
    return output;
}