我们通过下面这段代码来了解一下std::vector的动态扩容过程。 #include<iostream>#include<vector>intmain(){std::vector<int>vec;intcapacity=-1;std::cout<<"size: "<<vec.size()<<" capacity: "<<vec.capacity()<<std::endl;for(inti=0;i<500;i++){vec.push_back(i);if(capacity!=vec.capacit...
2 vector存放结构体类型变量的副本：#include <iostream>#include <string>#include <vector>//structtypedef struct student{ char school_name[100]; char gender;//xing bie int age; bool is_absent;} StudentInfo;typedef std::vector<StudentInfo> StudentInfoVec;//sheng mingvoid print(StudentInfoVec *...
int cConc[3][5]; std::array<std::array<int, 5>, 3> aConc; int **ptrConc; // initialized to [3][5] via new and destructed via delete std::vector<std::vector<int>> vConc; // initialized to [3][5]指向c样式数组（cConc）或std :: array（aConc）中第一个元素的指针可以...
1：array 定义的时候必须定义数组的元素个数;而vector 不需要；且只能包含整型字面值常量，枚举常量或者...
// constructing vectors#include<iostream>#include<vector>intmain(){// constructors used in the same order as described above:std::vector<int> first;// empty vector of intsstd::vector<int>second(4,100);// four ints with value 100std::vector<int>third(second.begin(),second.end());//...
比如 char *p=”sdflkjasljfsjlsdfsa”; char p1[200]; 将p赋给p1 （1）strcpy(p1,p)...
多维std :: vector不会在所有维度中打包。鉴于以下声明:int cConc[3][5];std::array<std::array<int, 5>, 3> aConc;int **ptrConc; // initialized to [3][5] via new and destructed ...
S() : p_impl(new impl) {} private: struct impl; boost::shared_ptr<impl> p_impl; }; 当您尝试通过以下方式将它们放入向量中时,会很有趣: std::vector<S> v(42); 现在,至少使用MSVC 8, v 中的所有元素都共享相同的 impl 成员。实际上,这是 ...
std::swap(std::vector) 特化 std::swap 算法(函数模板)erase(std::vector),erase_if(std::vector) (C++20) 擦除所有满足特定判别标准的元素(函数模板 cpp template<typenameT>classVector{public:Vector()noexcept=default;explicitVector(size_tn): cap_{n}, ptr_{alloc(cap_)} ...
usingnamespacestd; intmain() { vectormyVector; myVector.push_back(99); return0; } 如果有人试图在同时使用std::vector的项目中使用这个类,他们会得到一个错误“error C2872: ‘vector’: ambiguous symbol”。这是因为编译器无法决定客户端代码引用的向量是std::vector还是location.h中定义的vector对象。