具有优化查找的容器，如std :: map但非关联

Question

I have a big std::vector<int> where I have to get an iterator so that I can call other functions of it, like erase . Looping through the vector to find the element I'm searching for takes a lot of time.

std::map::find() is much faster, but I don't want to allocate memory for the second value which I'm never going to use.

Is there any single-value container with find() or anything that gives me an iterator with similar speed as std::map::find ? I couldn't find any.

Answer 1

您正在寻找std::set或std::multiset 。

Answer 2

您可以使用std::unordered_map或使用相同的std::vector来保留元素的顺序，您可以将标准算法应用于已排序的容器，例如std::equal_range 。