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[x]补 =1001 0011b
[-y]补 =1101 0011b(+
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[x-y]补 =0110 0110b
Cs♁Cp = 1♁0 = 1 ,负溢出
（Cs是符号位的进位,Cp是最高数值位的进位,♁表示异或）
[x-y]反 = -0110 0101b
[x-y]原 = -1001 1010b
x -y = -1001 1010b = -154d