Chapter 12: Operations on bits

Program 12.1, Page number: 282

In [1]:
def main():

        #Variable Declaration
        word1=77
        word2=150
        word3=210
        
        #Result
        print(word1&word2)
        print(word1&word1)
        print(word1&word2&word3)
        print(word1&1)

if __name__=='__main__':
        main()

4
77
0
1

Program 12.2, Page number: 286

In [2]:
def main():

        #variable Declarations
        w1=525
        w2=707
        w3=122
        
        print("{0:5}  {1:5}  {2:5}".format(w1&w2,w1|w2,w1^w2))
        print("{0:5}  {1:5}  {2:5}".format(~w1,~w2,~w3))
        print("{0:5}  {1:5}  {2:5}".format(w1^w1,w1&~w2,w1|w2|w3))
        print("{0:5}  {1:5}".format(w2&w3,w1|w2&~w3))
        print("{0:5}  {1:5}".format(~(~w1&~w2),~(~w1|~w2)))

        #Exchange variables
        w1^=w2
        w2^=w1
        w1^=w2
        print("w1={0:3}  w2={1:3}".format(w1,w2))


if __name__=='__main__':
        main()

  513    719    206
 -526   -708   -123
    0     12    767
   66    653
  719    513
w1=707  w2=525

Program 12.3, Page number: 288

In [3]:
def shift(value,n):
        if(n>0):
                value <<=n              #Left shift
        else:
                value >>=-n             #Right Shift

        return value

def main():
        #Variable Declaration
        w1=177777
        w2=444

        #Result
        print("{0:7}   {1:7}".format(shift(w1,5),w1<<5))
        print("{0:7}   {1:7}".format(shift(w1,-6),w1>>6))
        print("{0:7}   {1:7}".format(shift(w2,0),w2>>0))
        print("{0:7} ".format(shift(shift(w1,-3),3)))

if __name__=='__main__':
        main()

5688864   5688864
   2777      2777
    444       444
 177776

Program 12.4, Page number: 290

In [4]:
def rotate(value,n):

        #Calculation
        if(n>0):
                n=n%32
        else:
                n=-(-n%32)

        if(n==0):
                result=value
        elif(n>0):
                bits=value>>(32-n)
                result=value<<n|bits
        else:
                n=-n
                bits=value<<(32-n)
                result=value>>n|bits

        return result


def main():
        w1=0xabcdef00
        w2=0xffff1122

        print("%x"%rotate(w1,8))
        print("%x"%rotate(w1,-16))
        print("%x"%rotate(w2,4))
        print("%x"%rotate(w2,-2))
        print("%x"%rotate(w1,0))
        print("%x"%rotate(w1,44))
        

if __name__=='__main__':
        main()

abcdef00ab
abcdef00abcd
ffff1122f
3fffc448bfffc448
abcdef00
abcdef00abc