Need help...solve this with steps...want the explanation plz..its urgent

Question

int a= 5;
a-=(a--)-(--a);

Answer 1

a = 5
a -= a-- - --a
a-- -> first use, then decrement
a -= 5 - --a
--a -> first decrement, then use, note* a has not yet been decremented by previous prefix.
a -= 5 - 4 , a = 4
a -= 1, a = 4
4 -= 1
also denoted:
a = 4 - (1)
a = 3

Answer 2

thanx☺