#include <string>
#include <iterator>
#include <iostream>
#include <algorithm>
using namespace std;
int main()
{
    string test = "TEST";
    string test2 = "TEST2";

    // This (only?) works on Visual Studio
    transform(test2.begin(), test2.end(), test2.begin(), tolower);

    // :: global namespace for clib tolower
    transform(test.begin(), test.end(), test.begin(), ::tolower);

    cout << test2 << endl;
    cout << test << endl;
    return 0;
}