这里最重要的是要理解erase成员函数,它删除了itVect迭代器指向的元素,并且返回要被删除的itVect之后的迭代器,迭代器相当于一个智能指 针,指向容器中的元素,现在删除了这个元素,将导致内存重新分配,相应指向这个元素的迭代器之后的迭代器就失效了,但erase成员函数返回要被删除的 itVect之后的迭代器。 1.手工编写for
st.erase(key); Removes the specified key if present. Average Time Complexity: 𝓞(1) Worst Time Complexity: O(n) st.find(key); Returns an iterator pointing to the key. If the key is not present, returns st.end(). Average Time Complexity: 𝓞(1) Worst Time Complexity: O(n) st....
然后使用unique,他可以将相邻的重复元素,全部放到vector后面,并且返回第一个重复数据的指针,最后将重复数据的元素,用erase删掉即可。 #include<iostream> #include<algorithm> #include<vector> using namespace std; vector<int> input; int n; int main() { cin>>n; for(int i=1;i<=n;i++) { int ...
std::unordered_mapis an associative container that contains key-value pairs with unique keys. Search, insertion, and removal of elements have average constant-time complexity. Internally, the elements are not sorted in any particular order, but organized into buckets. Which bucket an element is pl...
Provides std::erase and/or std::erase_if for a variety of STL containers such as string, list, vector, map, etc.For erasing by value use std::erase, or to specify a predicate when to erase elements use std::erase_if. Both functions return the number of erased elements....
元素添加和删除:可以使用push_back()函数在vector的末尾添加元素,使用pop_back()函数删除末尾的元素.还可以使用insert()函数在指定位置插入元素,使用erase()函数删除指定位置的元素. 容器大小管理:可以使用size()函数获取vector中元素的数量,使用empty()函数检查vector是否为空.还可以使用resize()函数调整vector的大小....
STL中的容器按存储方式分为两类,一类是按以数组形式存储的容器(如:vector 、deque);另一类是以不连续的节点形式存储的容器(如:list、set、map)。在使用erase方法来删除元素时,需要注意一些问题。 在使用 list、set 或 map遍历删除某些元素时可以这样使用: ...
Complexity 1)Constant. 2)Linear in the distance betweenfirstandlast. Notes When container elements need to be erased based on a predicate, rather than iterating the container and calling unaryerase, the iterator range overload is generally used withstd::remove()/std::remove_if()to minimise th...
Provides std::erase and/or std::erase_if for a variety of STL containers such as string, list, vector, map, etc.For erasing by value use std::erase, or to specify a predicate when to erase elements use std::erase_if. Both functions return the number of erased elements....
Vulkan A low-level API that removes many of the abstractions found in previous generation graphics APIs. This is great for delivering maximum performance, but has the side effect of exposing more complexity to the developer. Fortunately, several excellent tutorials exist to help clear this hurdle ...