迭代器的妙用

例如：实现数列求和

#include<bits/stdc++.h>
using namespace std;
struct node{
	int val;
	node& operator = (int v){
		val += v;
		return *this;
	}
};
struct iter{

	using value_type = node;
	using reference = value_type&;
	using pointer = value_type*;
	using iterator_category = output_iterator_tag;
	using difference_type = int;
	
	node* val;
	iter(node& pos) : val(&pos){}
	node& operator *(){
		return *val;
	}
	void operator ++(){}
};
int main(){
	node s = {0};
	iter it(s);
	cout << s.val << endl;
	vector<int> v = {1, 2, 4, 5};
	copy(v.begin(), v.end(), it);
	cout << s.val <<endl;
	return 0;
}

只要坚持良好码风，再也不用担心别人能看懂我的代码了。