c++ - 在遍历 vector 时从 vector 中删除对象

Question

我是 C++ 的新手，所以我无法弄清楚如何最好地从 vector 中删除一个对象，同时仍然迭代它。

基本上，我需要遍历两个 vector 。对于每个项目，如果 ID 匹配，我可以删除它们。

//For every person, check to see if the available bags match:
        for(std::vector<Person>::iterator pit = waitingPeopleVector.begin(); pit != waitingPeopleVector.end(); ++pit) {
            for(std::vector<Bag>::iterator bit = waitingBagsVector.begin(); bit != waitingBagsVector.end(); ++bit) {
                int pId = pit->getId();
                int bId = bit->getId();
                if(pId == bId){
                    //a match occurs, remove the bag and person
                }
            }
        }

使用迭代器有点困惑，我知道我可以在我的 vector 上使用 .erase() 函数，但我不能真正通过 pit 或 位。任何帮助表示赞赏。谢谢

Answer 1

来自标准:

The iterator returned from a.erase(q) points to the element immediately following q prior to the element being erased. If no such element exists, a.end() is returned.

我会在类似使用 erase 方法的地方使用它:

std::vector<Person>::iterator pit = waitingPeopleVector.begin();
std::vector<Bag>::iterator bit = waitingBagsVector.begin();

while (pit != waitingPeopleVector.end())
{
    bool didit;

    while (bit != waitingBagsVector.end())
    {
        didit = false;
        if (pit->getId() == bit->getId() && !didit)
        {
            bit = waitingBagsVector.erase(bit);
            pit = waitingPeopleVector.erase(pit);
            didit = true;
        }
        else
        {
            ++bit;
        }
    }

    if (didit)
        continue;
    else
        ++pit;
}