1. a -= (++b - c); a -= (3-1); a -= 2; a= 0; // a = 0; b = 3; c = 1.
2. b += a++; b +=1; b = 3; // a = 1; b =3; c = 1.
3. a -= --c; a -= 0; a = 1; // a = 1; b = 3; c = 0.
4. b += b + c; b += 3 + 0; b += 3; b = 6 // a = 1; b= 6; c = 0.
Ответ: a = 1; b= 6; c = 0.