remove(b,e,v) //[b,e) 删value
remove_if(b,e,p) //[b,e) 删p条件
remove_copy(b,e,r,v) //[b,e) 删v，结果存入r
remove_copy_if(b,e,r,p) //[b,e) 删p条件，结果存入r

remove和remove_if结果相同，只是传入的条件不一样。示例图如下：

remove_copy和remove_copy_if会把pass的元素保存在目标迭代器，而不是直接在原始数据上修改。

#include <iostream>
#include <string>
#include<vector>
#include <algorithm>
using namespace std;

template<typename T>
void Print(T& v) {
	typename T::iterator iter = v.begin();
	while (iter != v.end()) {
		cout << *iter++ << " ";
	}
	cout << endl;
}

bool condition(int x) {
	return x == 2;
}
int main() {

	cout << "测试remove" << endl;
	int data[] = {1,3,2,3,2,1,3,2};
	vector<int> vec(data, data + 8);
	vector<int>::iterator ivec, it;
	ivec = remove(vec.begin(), vec.end(), 2);
	for (it = vec.begin(); it != ivec; it++) {
		cout << *it << " ";
	} //打印1 3 3 1 3
	cout << endl;
	cout << "实际数据是" << endl;
	Print(vec); //打印1 3 3 1 3 1 3 2
	cout << endl;


	cout << "测试remove_if" << endl;
	int data3[] = { 1,3,2,3,2,1,3,2 };
	vector<int> vec3(data3, data3 + 8);
	vector<int>::iterator ivec3, it3;
	ivec3 = remove_if(vec3.begin(), vec3.end(), condition);
	for (it3 = vec3.begin(); it3 != ivec3; it3++) {
		cout << *it3 << " ";
	}//打印1 3 3 1 3
	cout << endl;
	cout << "实际数据是" << endl;
	Print(vec3);//打印1 3 3 1 3 1 3 2
	cout << endl;


	cout << "测试remove_copy" << endl;
	int data2[] = { 1,3,2,3,2,1,3,2 };
	vector<int> vec2(data2, data2 + 8);
	vector<int>::iterator ivec2, it2;
    vector<int> myvec2(8);
	ivec2 = remove_copy(vec2.begin(), vec2.end(), myvec2.begin(), 2);
	for (it2 = vec2.begin(); it2 != ivec2; it2++) {
		cout << *it2 << " ";
	}//打印1 3 3 1 3
	cout << endl;
	cout << "实际数据是" << endl;
	Print(vec2);//打印1 3 2 3 2 1 3 2 
	cout << endl;
	
	
	cout << "测试remove_copy_if" << endl;
	int data4[] = { 1,3,2,3,2,1,3,2 };
	vector<int> vec4(data4, data4 + 8);
	vector<int>::iterator ivec4, it4;
	ivec4 = remove_copy_if(vec4.begin(), vec4.end(), vec4.begin(), condition);
	for (it4 = vec4.begin(); it4 != ivec4; it4++) {
		cout << *it4 << " ";
	}
	cout << endl;//打印1 3 3 1 3
	cout << "实际数据是" << endl;
	Print(vec4);//打印1 3 2 3 2 1 3 2 

	return 0;
}