#include <iostream>
#include <clocale>
#include <cwctype>
#include <cstdlib>
int main()
{
std::setlocale(LC_ALL, "en_US.utf8");
char utf8[] = {'\xc3', '\x81'};
wchar_t big;
std::mbtowc(&big, utf8, sizeof utf8);
// or just skip the whole utf8 conversion
// wchar_t big = L'Á';
wchar_t small = std::towlower(big);
std::wcout << "Big: " << big << '\n'
<< "Small: " << small << '\n';
}
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