[x]原 =1010 0110 0110 1101
[x]反 =1101 1001 1001 0010
[x]補 =1101 1001 1001 0011
y =3456 = +1101 1000 0000
[y]補 =0000 1101 1000 0000
[-y]原=1000 1101 1000 0000
[-y]反=1111 0010 0111 1111
[-y]補=1111 0010 1000 0000
.
..[x]補 =1101 1001 1001 0011
..[y]補 =0000 1101 1000 0000 (+
------------------------------------------
[x+y]補 =1110 0111 0001 0011
Cs⊕Cp = 0⊕0 = 0 無溢出,
(Cs是符號位的進位,Cp是最高數值位的進位,⊕表示異或)
[x+y]反 =1110 0111 0001 0010
[x+y]原 =1001 1000 1110 1101
x+y = - 1 1000 1110 1101 = -6381
.
..[x]補 =1101 1001 1001 0011
.[-y]補 =1111 0010 1000 0000 (+
------------------------------------------
[x-y]補 =1100 1100 0001 0011 符號位進位自然丟失
Cs⊕Cp = 1⊕1 = 0 無溢出,
[x-y]反 =1100 1100 0001 0010
[x-y]原 =1011 0011 1110 1101
x-y = - 11 0011 1110 1101 = -13293