Easiest way to convert int to string in C

Question

In C++, what is the simplest way to convert an int to an equivalent string? 

I'm aware of two approaches. 

Is there any other option?

(1)

int a = 10;
char *intStr = itoa(a);
string str = string(intStr);

(2)

int a = 10;
stringstream ss;
ss << a;
string str = ss.str();

Answer 1

std::stoi (and variations for each numeric type) and std::to string, the C++11 equivalents of atoi and itoa, but stated in terms of std::string, are introduced.

#include <string> 

std::string s = std::to_string(42);

As a result, this is the quickest route I can think of. 

You may even use the auto keyword to avoid identifying the type.

auto s = std::to_string(42);