我可以重用已写入的变量吗？

Question

功能代码：

std::set<OutputData> results;
OutputData od;
    for (unsigned int qt = 0; qt < sizeof(allResultTypes); qt++)
    {
            //for each ResultType loop through all dates (Labels property)
            for (unsigned int i = 0; i < sizeof(allDates[i]); i++)
            {

                //write date to the ExposureData object
                od.date = JsonParser::allLabels[i];

                if (allResultTypes[qt] == "type_A")
                {
                    od.type_A = allData[i];
                }

                if (allResultTypes[qt] == "type_B")
                {
                    od.type_B = allData[i];
                }

                results.insert(od);
            }       
    }

输出数据类;

struct OutputData
{
    int32_t date;
    double type_A;
    double type_B;
};

问题：

1）一旦将od插入到结果集中，我可以擦除od变量的内容吗？我想以这种方式重用od对象;

for (unsigned int i = 0; i < sizeof(allDates[i]); i++)
            {
                if (od != nullptr) 
                {
                    od.date = nullptr;
                    od.type_A = nullptr;
                    od.type_B = nullptr;
                }
                //write date to the ExposureData object
                od.date = JsonParser::allLabels[i];

                if (allResultTypes[qt] == "type_A")
                {
                    od.type_A = allData[i];
                }
                if (allResultTypes[qt] == "type_B")
                {
                    od.type_B = allData[i];
                }
                results.insert(od);
            }      

这是正确的还是我取消了前面循环迭代添加的set的内容？