Convert a string to an integer using a stringstream

#include <sstream>
#include <iostream>  //used for cout
int main()
{
    const char* str = "12345";
    std::stringstream ss( str );
    int i;
    ss >> i;
    if (ss.fail())
    {
        // Error
    }
    else
    {
        std::cout << "The integer value is: " << i;
    }
    return 0;
}

#include <sstream>
#include <iostream>  //used for cout
int main()
{
    std::string str = "12345";
    std::istringstream ss(str);
    int i;
    ss >> i;
    if (ss.fail())
    {
        // Error
    }
    else
    {
        std::cout << "The integer value is: " << i;
    }
    return 0;
}