C++ for (auto &it:myset) &是什么意思 引用

Posted 2022-01-06 软件工程小施同学

加了&代表引用，如果不加，则是值拷贝

 

#include <iostream>
#include <set>

using namespace std;

int main()

	
    // cbegin/cend(c++11): Returns a const_iterator pointing to the first element in the container/
	// Returns a const_iterator pointing to the past-the-end element in the container
	std::set<int> myset =  50, 20, 60, 10, 25 ;
 
	std::cout << "myset contains:";
	for (auto it:myset)
		std::cout << ' ' << it;
	
	std::cout << '\\n';
	
	std::cout << "myset contains:";
	for (auto &it:myset)
		std::cout << ' ' << it;

	system("pause");
	return 0;