Question

我有一个类型为words_in_family的向量vector<vector<string>>。我试图删除words_in_family中不等于字符串向量largest_family的每个元素，但是遇到问题并且不确定原因。任何帮助表示赞赏。

for (int i = words_in_family.size() - 1; i >= 0; i--)
{
    if (words_in_family[i] != largest_family)
    {
        words_in_family.erase(words_in_family[i]);
    }
}

Answer 1

erase方法没有取值。而是使用迭代器作为erase方法的参数：

vector<vector<string>>::iterator it = words_in_family.begin();
for (int i = words_in_family.size() - 1; i >= 0; i--)
{
    if (words_in_family[i] != largest_family)
    {
        words_in_family.erase(it+i);
    }
}

迭代器擦除（迭代器位置）; 迭代器擦除（迭代器优先，迭代器最后）;

请注意，std :: vector的迭代器是随机访问迭代器，因此您可以添加/减去整数值以获取其他有效迭代器。

Answer 2

C ++ std::vector擦除一个元素，在你的情况下：

删除值等于words_in_family的向量（largest_family）中的元素：

std::vector<std::vector<std::string>>::iterator Itr;
for(Itr = Words_in_family.begin(); Itr != Words_in_family.end();)
{
    if(*Itr == largest_family)
    {
        Itr = Words_in_family.erase(Itr);
    }
    else
    {
        Itr++;
    }
}

Answer 3

words_in_family.erase(words_in_family.begin()+i, words_in_family.begin()+i+1);

erase将迭代器作为参数

从Vector Inside Loop中删除元素

3 个答案: