shared: bool flag[] = { false, false };
        // Do I want to be in the C.S.
        int turn = 0;
        // Whose turn is it


  Process 0                |   Process 1
---------------------------+--------------------------
  flag[0] = true;          |   flag[1] = true;
  turn = 1;                |   turn = 0;
  while (flag[1] &&        |   while (flag[0] &&
         turn == 1)        |          turn == 0)
    pause();               |      pause();
  C.S.                     |   C.S.
  flag[0] = false;         |   flag[1] = false;
                           |

(Peterson's algorithm)