drink.c

// To compile, use: https://github.com/arthaud/c2bf
int read = 0;
while (true) {
  read = read_char();

  if (read == 'f') {
    write_char('d');
    write_char('r');
    write_char('i');
    write_char('n');
    write_char('k');
  }
  if (read == 'e') {
    write_char('r');
    write_char('e');
    write_char('f');
    write_char('i');
    write_char('l');
    write_char('l');
  }
}