int* data; // 存储数据的指针 int size; // 当前存储的元素个数 int capacity; // 当前分配的内存空间大小 } Vector; // 初始化 vector void vector_init(Vector* v) { v->size = 0; v->capacity = 1; v->data = (int*) malloc(sizeof(int) * v->capacity); } // 释放 vector 占用的...
#include<iostream>#include<vector>using namespace std;/* * 结论: * capacity = 1, newcapacity = 2; * capacity > 1, newcapacity = (int)(capacity * 1.5); */intmain(){int cap=-1;vector<int>ints;for(int i=0;i<1000000;i++){ints.push_back(i);if(cap!=ints.capacity()){cap=...
std::vector<int> first;//default(1)std::vector<int> second(4,100);//fill(2)std::vector<int> third(second.begin(), second.end());//range(3)std::vector<int> fourth(third);//copy(4)//the iterator constructor can also be used to construct from arrays:intmyints[] = {16,2,77,...
Template>:std::true_type{};intmain(){constexprboolis_vec=is_specialization<std::vector<int>,st...
vector<int> ::const_iterator end_iter = a.end(); // 获取最后一个元素迭代器的下一个地址一 a.push_back(100); //尾插 a.pop_back(); //尾删 int size = a.size(); //个数 int capacity = a.capacity(); //容量 bool isEmpty = a.empty(); //判断是否为空 ...
v1.capacity() // v1现有的在存储容量(不再一次进行扩张内存空间的前提下) v1.empty() // 判断v1是否为空 v1.max_size() // 返回vector可以存放的最大元素个数,一般这个数很大,因为vector可以不断调整容量大小。 v1.shrink_to_fit() // 该函数会把v1的capacity()的大小压缩到size()大小,即释放多...
#include <iomanip> #include <iostream> #include <vector> int main() { int sz = 100; std::vector<int> v; auto cap = v.capacity(); std::cout << "Initial size: " << v.size() << ", capacity: " << cap << '\n'; std::cout << "\nDemonstrate the capacity's growth policy...
Here’s the same example as before, but with an added call to reserve() to set the capacity: #include <iostream> #include <vector> void printStack(const std::vector<int>& stack) { if (stack.empty()) // if stack.size == 0 std::cout << "Empty"; for (auto element : stack) ...
std::vector<T,Allocator>::rend, std::vector<T,Allocator>::crend std::vector<T,Allocator>::empty std::vector<T,Allocator>::size std::vector<T,Allocator>::max_size std::vector<T,Allocator>::reserve std::vector<T,Allocator>::capacity std::vector<T,Allocator>::shrink_to_fit std::vecto...
vector 之所以比较容易变成constexpr, 原因大概还是因为内存分布简单。vector 本身是 连续内存上的顺序容器...