find vs at, C++ (vc++)

find vs at

//Microsoft (R) C/C++ Optimizing Compiler Version 19.00.23506 for x64

/*
	iterator find(const key_type& _Keyval)
		{	// find an element in mutable sequence that matches _Keyval
		iterator _Where = lower_bound(_Keyval);
		return (_Where == end()
			|| _DEBUG_LT_PRED(this->_Getcomp(),
				_Keyval, this->_Key(_Where._Mynode()))
					? end() : _Where);
		}

mapped_type& at(const key_type& _Keyval)
		{	// find element matching _Keyval
		iterator _Where = _Mybase::lower_bound(_Keyval);
		if (_Where == _Mybase::end()
			|| _Mybase::_Getcomp()(_Keyval, _Mybase::_Key(_Where._Mynode())))
			_Xout_of_range("invalid map<K, T> key");
		return (_Where->second);
		}

#include <vector>
#include <iostream>
#include <chrono>
#include <map>

void f(const std::map<int, int>& v)
{
	const auto& it = v.find(0);
}

void g(const std::map<int, int>& v)
try
{
	v.at(0);
}
catch (...)
{
	return;
}

void test1(const std::map<int, int>& a)
{
	{
		auto start = std::chrono::system_clock::now();
		for (int i = 0; i < 100000; i++)
		{
			f(a);
		}
		auto seconds = std::chrono::duration<double>(std::chrono::system_clock::now() - start);
		std::cout << seconds.count() << std::endl;
	}

{
		auto start = std::chrono::system_clock::now();
		for (int i = 0; i < 100000; i++)
		{
			g(a);
		}
		auto seconds = std::chrono::duration<double>(std::chrono::system_clock::now() - start);
		std::cout << seconds.count() << std::endl;
	}
}

int main()
{
	std::map<int, int> a;
	test1(a);

a[0] = 1;
	test1(a);

std::cout << "a";
    return 0;
}

/*
Coll
*/


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