Why printf doesn't print what I feed it with?

Question

printf("%s\n", "ああ");

It outputs :

ã‚ã‚

What else should I do to print it correctly?

Answer 1

Assuming that's unicode, compile with a C99 compiler

#include <locale.h>
#include <stdio.h>
#include <wchar.h>

int main(void) {
  wchar_t buff[3]; // = L"ああ";
  buff[0] = buff[1] = L'\U00003042';
  buff[2] = 0;
  setlocale(LC_ALL, "");
  wprintf(L"%ls\n", buff);
  return 0;
}