错误：无法取消引用值初始化的向量迭代器

Question

错误：无法取消引用值初始化的向量迭代器

当我尝试引用迭代器时

/*
* e.g. ["1","2","3"] will produce => [ ["1","2","3"], ["2","3","1"], ["3","1","2"],]
*/
vector<vector<string>> getRotation(vector<string> in) {

    size_t num_rotation = in.size() - 1;

    vector<string> variantion(in);
    vector<vector<string>> result{ in };

    for (size_t i = 0; i < num_rotation; i++)
    {
        vector<string>::iterator temp = variantion.begin();
        string tempValue = *temp; // Error: can't dereference value-initialized vector iterator

        // variantion remove the first element ,and append to the end
        variantion.erase(temp);
        variantion.push_back(tempValue);

        result.push_back(variantion);
    }

    return result;
}

Answer 1

它最终使我的参数的大小为0，因此此代码为我返回了一个空迭代器

        vector<string>::iterator temp = variantion.begin();

我认为这就是它引发错误的原因。