CZOS
0000
0001
0010
0011
0100
...
1111


Q9 of practice exam 1

        1011 0101
        0110 1110
        =========
        1101 1011
       11111 1  0
        =========
        0010 0011
        
        b7
        7f
        --
       136
       
       
       0xb7 = 11*16+7
            = 176+7
            = 183
            
           -(256-183)=  -73
           
           
           n-bit width
           C2(x) = C1(x) + 1
                 = (2^n-1)-x + 1
                 = 2^n - 1 - x + 1
                 = 2^n - x
                 
                 
    1111 1111
 -  0101 1100
    =========
    1010 0011
    
    
Q12

     100
      e5
     ---
     01b
     
     
=============================================
section 6.2 of the textbook

  jg L1
  
  jg jump iff (not L) and (not Z)
              (S == O) and (not Z)
              ((S==1 and O==1) or
              (S==0 and O==0)) and
              (not Z)
              
   jz X1
   js C1
   # s=0
   jo X1
C1:
   # s=1
   jo L1
X1:

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