<span data-docs-delta="[[20&#44;   " 一、什么是="" vector"&#44;  ="" "0:\"rgba(0%2c%200%2c%200%2c%200.85)\"|31:2|inline-dir:\"ltr\""]&#44;  ="" [20&#44;  ="" "\n"&#44;  ="" "24:\"ndqk\"|32:2|direction:\"ltr\""]&#44;  ="" "向量（vector）是一个顺序容器（sequence="" container），它能够存放各种类型的对象。可以简单的认为，向量是一个能够存放任意类型的动态数组（元素个数可变）"&#44;  ="" "0:\"rgba(0%2c%200%2c%200%2c%200.85)\"|27:\"12\"|31:2|inline-dir:\"ltr\""]&#44;  ="" "24:\"gqtl\"|direction:\"ltr\""]&#44;  ="" "二、vector的常见函数"&#44;  ="" "24:\"mfzz\"|32:2|direction:\"ltr\""]&#44;  ="" [30&#44;  ="" [{"a1":[40&#44;  ="" [[20&#44;  ="" "函数名"&#44;  ="" "26:\"54772603\"|8:1|inline-dir:\"ltr\""]&#44;  ="" "24:\"rmtl\"|7:1|direction:\"ltr\""]]&#44;  ="" "25:\"qkmh\""]&#44;  ="" "a2":[40&#44;  ="" "push_back(元素)"&#44;  ="" "26:\"54772603\"|inline-dir:\"ltr\""]&#44;  ="" "24:\"fxgy\"|7:1|direction:\"ltr\""]]&#44;  ="" "25:\"htru\"|7:1"]&#44;  ="" "a3":[40&#44;  ="" "insert(位置，元素)"&#44;  ="" "24:\"wst2\"|7:1|direction:\"ltr\""]]&#44;  ="" "25:\"1bfb\"|7:1"]&#44;  ="" "a4":[40&#44;  ="" "insert(位置，个数n，元素)"&#44;  ="" "24:\"4lsb\"|7:1|direction:\"ltr\""]]&#44;  ="" "25:\"bcid\"|7:1"]&#44;  ="" "a5":[40&#44;  ="" "insert(位置，向量头指针first，向量尾指针end)"&#44;  ="" "24:\"wobu\"|7:1|direction:\"ltr\""]]&#44;  ="" "25:\"ej20\"|7:1"]&#44;  ="" "a6":[40&#44;  ="" "erase（位置）"&#44;  ="" "24:\"4n2m\"|7:1|direction:\"ltr\""]]&#44;  ="" "25:\"ftmy\"|7:1"]&#44;  ="" "a7":[40&#44;  ="" "erase（开始位置，结束位置）"&#44;  ="" "24:\"tuym\"|7:1|direction:\"ltr\""]]&#44;  ="" "25:\"jbzp\"|5:1|7:1"]&#44;  ="" "a8":[40&#44;  ="" "pop_back(="" )"&#44;  ="" "24:\"pdew\"|7:1|direction:\"ltr\""]]&#44;  ="" "25:\"xedm\"|5:1|7:1"]&#44;  ="" "a9":[40&#44;  ="" "clear(="" "24:\"lmx8\"|7:1|direction:\"ltr\""]]&#44;  ="" "25:\"fki5\"|5:1|7:1"]&#44;  ="" "a10":[40&#44;  ="" "运算符[="" i="" ]"&#44;  ="" "24:\"uwak\"|7:1|direction:\"ltr\""]]&#44;  ="" "25:\"nvxq\"|5:1|7:1"]&#44;  ="" "a11":[40&#44;  ="" "front(="" "24:\"know\"|7:1|direction:\"ltr\""]]&#44;  ="" "25:\"kye5\"|5:1|7:1"]&#44;  ="" "a12":[40&#44;  ="" "back(="" "24:\"zrxl\"|7:1|direction:\"ltr\""]]&#44;  ="" "25:\"mpqs\"|5:1|7:1"]&#44;  ="" "a13":[40&#44;  ="" "begin(="" "24:\"fo9f\"|7:1|direction:\"ltr\""]]&#44;  ="" "25:\"5aen\"|5:1|7:1"]&#44;  ="" "a14":[40&#44;  ="" "end(="" "24:\"yuyo\"|7:1|direction:\"ltr\""]]&#44;  ="" "25:\"e3gj\"|5:1|7:1"]&#44;  ="" "a15":[40&#44;  ="" "rbegin(="" "24:\"hgpy\"|7:1|direction:\"ltr\""]]&#44;  ="" "25:\"ogez\"|5:1|7:1"]&#44;  ="" "a16":[40&#44;  ="" "rend(="" )="" "&#44;  ="" "24:\"rvva\"|7:1|direction:\"ltr\""]]&#44;  ="" "25:\"2r8y\"|5:1|7:1"]&#44;  ="" "a17":[40&#44;  ="" "size(="" "24:\"ppmf\"|7:1|direction:\"ltr\""]]&#44;  ="" "25:\"fshh\"|5:1|7:1"]&#44;  ="" "a18":[40&#44;  ="" "resize(大小)"&#44;  ="" "24:\"xnjl\"|7:1|direction:\"ltr\""]]&#44;  ="" "25:\"ubec\"|5:1|7:1"]&#44;  ="" "a19":[40&#44;  ="" "max_size(="" "24:\"otfc\"|7:1|direction:\"ltr\""]]&#44;  ="" "25:\"ih0c\"|5:1|7:1"]&#44;  ="" "a20":[40&#44;  ="" "empty(="" "24:\"am56\"|7:1|direction:\"ltr\""]]&#44;  ="" "25:\"epcl\"|5:1|7:1"]&#44;  ="" "a21":[40&#44;  ="" "swap(="" "24:\"0xn1\"|7:1|direction:\"ltr\""]]&#44;  ="" "25:\"mz9t\"|5:1|7:1"]&#44;  ="" "b1":[40&#44;  ="" "函数说明"&#44;  ="" "24:\"vxil\"|7:1|direction:\"ltr\""]]&#44;  ="" "25:\"qmvz\""]&#44;  ="" "b2":[40&#44;  ="" "增加一个元素到向量后面"&#44;  ="" "24:\"y0z0\"|direction:\"ltr\""]]&#44;  ="" "25:\"57dl\""]&#44;  ="" "b3":[40&#44;  ="" "插入元素到向量的指定位置"&#44;  ="" "24:\"ckqi\"|direction:\"ltr\""]]&#44;  ="" "25:\"drwa\""]&#44;  ="" "b4":[40&#44;  ="" "插入n个相同的元素到指定位置"&#44;  ="" "24:\"ui8y\"|direction:\"ltr\""]]&#44;  ="" "25:\"3bgw\""]&#44;  ="" "b5":[40&#44;  ="" "将另一个向量从first位置开始到结束（不包括end）之间的内容插入该向量的指定位置"&#44;  ="" "24:\"zjr6\"|direction:\"ltr\""]]&#44;  ="" "25:\"1w96\""]&#44;  ="" "b6":[40&#44;  ="" "删除指定位置的元素"&#44;  ="" "24:\"0npv\"|direction:\"ltr\""]]&#44;  ="" "25:\"1rmk\""]&#44;  ="" "b7":[40&#44;  ="" "删除向量中[first&#44;  ="" last)中元素"&#44;  ="" "24:\"u43v\"|direction:\"ltr\""]]&#44;  ="" "25:\"v79e\"|5:1"]&#44;  ="" "b8":[40&#44;  ="" "弹出（删除）向量的最后一个元素"&#44;  ="" "24:\"j4ly\"|direction:\"ltr\""]]&#44;  ="" "25:\"ehvt\"|5:1"]&#44;  ="" "b9":[40&#44;  ="" "清除向量的所有元素，size()变为0"&#44;  ="" "24:\"8rkp\"|direction:\"ltr\""]]&#44;  ="" "25:\"mx7p\"|5:1"]&#44;  ="" "b10":[40&#44;  ="" "取向量下标为i的元素"&#44;  ="" "24:\"lczc\"|direction:\"ltr\""]]&#44;  ="" "25:\"iv74\"|5:1"]&#44;  ="" "b11":[40&#44;  ="" "取向量的第一个元素"&#44;  ="" "24:\"07tf\"|direction:\"ltr\""]]&#44;  ="" "25:\"lusa\"|5:1"]&#44;  ="" "b12":[40&#44;  ="" "取向量的最后一个元素"&#44;  ="" "24:\"rgmw\"|direction:\"ltr\""]]&#44;  ="" "25:\"k8nq\"|5:1"]&#44;  ="" "b13":[40&#44;  ="" "返回向量头指针（迭代器）指向第一个元素"&#44;  ="" "24:\"qlwr\"|direction:\"ltr\""]]&#44;  ="" "25:\"rbxx\"|5:1"]&#44;  ="" "b14":[40&#44;  ="" "返回向量尾指针，指向向量最后一个元素的下一个位置"&#44;  ="" "24:\"aufz\"|direction:\"ltr\""]]&#44;  ="" "25:\"7zbc\"|5:1"]&#44;  ="" "b15":[40&#44;  ="" "反向迭代器，指向最后一个元素"&#44;  ="" "24:\"wiqn\"|direction:\"ltr\""]]&#44;  ="" "25:\"psh1\"|5:1"]&#44;  ="" "b16":[40&#44;  ="" "反向迭代器，指向第一个元素之前的位置"&#44;  ="" "24:\"pwsa\"|direction:\"ltr\""]]&#44;  ="" "25:\"ujl3\"|5:1"]&#44;  ="" "b17":[40&#44;  ="" "返回"&#44;  ="" "24:\"s1qc\"|direction:\"ltr\""]]&#44;  ="" "25:\"xkdr\"|5:1"]&#44;  ="" "b18":[40&#44;  ="" "重新设定向量的大小，也就是保存元素的个数"&#44;  ="" "24:\"yosp\"|direction:\"ltr\""]]&#44;  ="" "25:\"glmc\"|5:1"]&#44;  ="" "b19":[40&#44;  ="" "得到vector最大可以是多大"&#44;  ="" "24:\"y8xh\"|direction:\"ltr\""]]&#44;  ="" "25:\"eouj\"|5:1"]&#44;  ="" "b20":[40&#44;  ="" "判断向量是否为空，等价于size(="" )为0"&#44;  ="" "24:\"musy\"|direction:\"ltr\""]]&#44;  ="" "25:\"wdau\"|5:1"]&#44;  ="" "b21":[40&#44;  ="" "交换两个同类型向量的数据"&#44;  ="" "24:\"yhb3\"|direction:\"ltr\""]]&#44;  ="" "25:\"iieb\"|5:1"]}&#44;  ="" [[10&#44;  ="" 21&#44;  ="" "26:\"54772603\""]]&#44;  ="" 2&#44;  ="" "3:308"]]]&#44;  ="" "25:\"jznvfd\"|readonly:false"]&#44;  ="" "对应于数组，要注意：向量的大小是可变的，开始时向量为空，随着不断插入元素，向量自动申请空间，容量变大。"&#44;  ="" "24:\"mndl\"|direction:\"ltr\""]&#44;  ="" "注意学会使用：sort="" ()、reverse="" ()="" 等函数对="" vector="" 进行排序、逆序等操作"&#44;  ="" "0:\"rgba(0%2c%200%2c%200%2c%200.85)\"|27:\"12\"|31:2|inline-dir:\"ltr\""]]"="" data-copy-origin="https://shimo.im">

一、什么是 vector

向量（vector）是一个顺序容器（Sequence Container），它能够存放各种类型的对象。可以简单的认为，向量是一个能够存放任意类型的动态数组（元素个数可变）

二、vector的常见函数

函数名	函数说明
push_back(元素)	增加一个元素到向量后面
insert(位置，元素)	插入元素到向量的指定位置
insert(位置，个数n，元素)	插入n个相同的元素到指定位置
insert(位置，向量头指针first，向量尾指针end)	将另一个向量从first位置开始到结束（不包括end）之间的内容插入该向量的指定位置
erase（位置）	删除指定位置的元素
erase（开始位置，结束位置）	删除向量中[first, last)中元素
pop_back( )	弹出（删除）向量的最后一个元素
clear( )	清除向量的所有元素，size()变为0
运算符[ i ]	取向量下标为i的元素
front( )	取向量的第一个元素
back( )	取向量的最后一个元素
begin( )	返回向量头指针（迭代器）指向第一个元素
end( )	返回向量尾指针，指向向量最后一个元素的下一个位置
rbegin( )	反向迭代器，指向最后一个元素
rend( )	反向迭代器，指向第一个元素之前的位置
size( )	返回
resize(大小)	重新设定向量的大小，也就是保存元素的个数
max_size( )	得到vector最大可以是多大
empty( )	判断向量是否为空，等价于size( )为0
swap( )	交换两个同类型向量的数据

1、什么是迭代器

迭代器（iterator）：用来指向、遍历、修改容器元素的变量，类似指针。

A、可遍历 STL 容器内全部或部分元素的对象

B、指出容器中的一个特定位置

</tr> </tbody> </table>

2、迭代器函数

#include 
using namespace std;
int main() {
//初始化
vectorpjc;//创建一个叫做pjc的向量
vectorjxy = {1,    2,    3,    4,    5,    6};
/*
增加：
容器名.push_back(元素)
容器名.insert(位置,   元素);
容器名.insert(位置,   n,   元素);  在位置插入n个元素
容器名.insert(位置,   容器的开始,   容器的结束);  在位置插入n个元素
*/
pjc.push_back(3);
pjc.push_back(2);
pjc.push_back(1);
pjc.insert(pjc.begin(),    jxy.begin() + 3,    jxy.end());
// for (int i = 0; i <= 5; i++) { // cout << pjc[i] << '\n'; // } /*删除 容器.erase(位置) 容器.erase(开始位置,   结束位置) 容器.pop_back() 默认删除最后一个位置的值 pjc.clear(); / / 修改 容器[位置]=新值 */ pjc[2] = 100; for (int i = 0; i <= 5; i++) { cout << pjc[i] << '\n'; } /*查询 容器.front() 容器.back() 容器.size() 容器.empty() */ cout << pjc.front() << '\n'; cout << pjc.back() << '\n'; cout << pjc.size() << '\n'; cout << pjc.empty() << '\n'; return 0; }

</span> 查看讲义和题解

操作	效果
* </td>	返回当前位置上的元素值。如果该元素有成员，可以通过迭代器以 operator -> 取用
++	将迭代器前进至下一元素
==和 !=	判断两个迭代器是否指向同一位置
=	为迭代器赋值，（将所指元素的位置赋值过去）