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remove由定义在 algorithm 头文件中的模板生成，所以要用它需要加上头文件#include?<algorithm>。
STL中remove（）只是将待删除元素之后的元素移动到vector的前端，而不是删除。若要真正移除，需要搭配使用erase()，才能真正删除。
#include <iostream>
#include <vector>
#include < algorithm >
using namespace std;
int main()
{
vector<int> mv = { 1,2,3,5,4,6,7,5,9 };
auto it = remove(mv.begin(), mv.end(), 5);
auto it1 =mv.erase(it, mv.end());
}添加运行结果：
#include <iostream>
#include <vector>
#include < algorithm >
using namespace std;
int main()
{
vector<int> mv = { 1,2,3,5,4,6,7,5,9 };
//vector<int> mv = { 1,2,3,5,4,6,7,5,9 };
cout << "my vector:" << endl;
for (auto tm = mv.begin(); tm != mv.end(); tm++)
{
cout << *tm << " ";
}
cout << endl;
auto it = remove(mv.begin(), mv.end(), 5);
cout << "after remove:" << endl;
if (it == mv.end())
{
for (auto tm = mv.begin(); tm != mv.end(); tm++)
{
cout << *tm << " ";
}
cout << endl;
}
else {
auto tm = mv.begin();
cout << "before iterator:" << endl;
for (; tm !=it; tm++)
{
cout << *tm << " ";
}
cout <<endl<< "after iterator:" << endl;
for (; tm != mv.end(); tm++)
{
cout << *tm << " ";
}
cout << endl;
}
auto it1 =mv.erase(it, mv.end());
cout << "after erase:" << endl;
if (it1 == mv.end())
{
for (auto tm = mv.begin(); tm != mv.end(); tm++)
{
cout << *tm << " ";
}
cout << endl;
}
else {
auto tm = mv.begin();
cout << "before iterator:" << endl;
for (; tm != it1; tm++)
{
cout << *tm << " ";
}
cout << "after iterator:" << endl;
for (; tm != mv.end(); tm++)
{
cout << *tm << " ";
}
cout << endl;
}
}运行结果如下：
?
?
erase函数原型有两种形式：
iterator erase(iterator position);
iterator erase(iterator first, iterator last);返回指向下一个元素的迭代器。
#include <iostream>
#include <vector>
using namespace std;
int main()
{
vector<int> vec = { 1,2,3,5,4,6,7,5,9 };
cout << "befor del 5:" << endl;
for (auto tm = vec.begin(); tm != vec.end(); tm++)
{
cout << *tm << " ";
}
cout << endl;
for (auto it = vec.begin(); it != vec.end();)
{
if (5 == *it) {
it = vec.erase(it);
}
else {
++it;
}
}
cout << "after del 5:" << endl;
for (auto tm = vec.begin(); tm != vec.end(); tm++)
{
cout << *tm << " ";
}
cout << endl;
}?运行结果：
?注意：
erase删除一个元素时，当前迭代器已经失效，需要让iterator迭代器指向下一个元素的迭代器，否则就会报错，自己可以试试，这里绝对是一个坑；
it = vec.erase(it);函数的语法格式：
InputIterator find (InputIterator first, InputIterator last, const T& val);其中，first 和 last 为输入迭代器，[first, last) 用于指定该函数的查找范围；val 为要查找的目标元素。
该函数适用于所有的序列式容器?
当 find() 函数查找成功时，其指向的是在 [first, last) 区域内查找到的第一个目标元素；如果查找失败，则该迭代器的指向和 last 相同。
头文件：
#include <algorithm> // std::find注意string类也有一个find函数，与stl的find算法有些不同，大家可以读读：C++ string中的find()函数 - 王陸 - 博客园 (cnblogs.com)?
#include <iostream>
#include <vector>
#include < algorithm >
using namespace std;
//删除说有满足条件的元素
void Del_1();
int main()
{
vector<int> mv = { 1,2,3,5,4,6,7,5,9 };
auto it = find(mv.begin(), mv.end(), 5);
if (it != mv.end())
{
mv.erase(it);
}
}添加打印信息：?
#include <iostream>
#include <vector>
#include < algorithm >
using namespace std;
//删除说有满足条件的元素
void Del_1();
int main()
{
vector<int> mv = { 1,2,3,5,4,6,7,5,9 };
//vector<int> mv = { 1,2,3,5,4,6,7,5,9 };
cout << "my vector:" << endl;
for (auto tm = mv.begin(); tm != mv.end(); tm++)
{
cout << *tm << " ";
}
cout << endl;
auto it = find(mv.begin(), mv.end(), 5);
cout << "after find:" << endl;
if (it == mv.end())
{
for (auto tm = mv.begin(); tm != mv.end(); tm++)
{
cout << *tm << " ";
}
cout << endl;
}
else {
auto tm = mv.begin();
cout << "before iterator:" << endl;
for (; tm != it; tm++)
{
cout << *tm << " ";
}
cout << endl << "after iterator:" << endl;
for (; tm != mv.end(); tm++)
{
cout << *tm << " ";
}
cout << endl;
}
if (it != mv.end())
{
auto it1=mv.erase(it);
cout << "after erase:" << endl;
if (it1 == mv.end())
{
for (auto tm = mv.begin(); tm != mv.end(); tm++)
{
cout << *tm << " ";
}
cout << endl;
}
else {
auto tm = mv.begin();
cout << "before iterator:" << endl;
for (; tm != it1; tm++)
{
cout << *tm << " ";
}
cout << endl << "after iterator:" << endl;
for (; tm != mv.end(); tm++)
{
cout << *tm << " ";
}
cout << endl;
}
}
}运行结果：?
?
参考文献：
C++ find()函数用法详解（超级详细） (biancheng.net)
在vector中，怎样删除某个指定值的元素
cs