这篇文章整理了vector.

Empirical Observation

1. make_move_iterator and push_back

std::vector::insert with std::make_move_iterator is generally faster than push_back in a loop theoretically. But it’s not. </br> I need to copy varible A(std::vector<pcl::Point>) to another varible B. I find that make_move_iterator is a little slower than push_back. Length of A is about 20000.

2. reserve

When copy or push large data to vector, reallocation will take much time. Using reserve to allocate sufficient capacity can reduce time cost significantly.

#include <vector>

member

1. erase

删除容器中的元素

erase(pos,n);     // 删除从pos开始的n个字符，比如erase(0,1)就是删除第一个字符
erase(position);  // 删除position处的一个字符(position是个string类型的迭代器)
erase(first,last);// 删除从first到last之间的字符（first和last都是迭代器）

1. iterator

#include <iterator>
// genarate a iterator for container c and this iterator will add element to c. c must support push_back
back_inserter(c);

// genarate a iterator for container c and this iterator will add element to c. c must support push_front
front_inserter(c);

// genarate a iterator for container c and add elemnet before it
inserter(c,it);

2 initailize vector

here.

reserve

When a std::vector is empty, calling std::vector::reserve is a constant-time operation, O(1).

indexing overhead.