Python includes exercises 55

Python 100 Li

Topic: Learn to use bitwise ~.

Program analysis: 0 = 1 ~; ~ 1 = 0;
(1) the right to make a four.
(2) set up a low-4 are all 1, the rest are all zero numbers. Available ~ (~ 0 << 4)
(3) both of the above will be the & operator.

Source Code:

#!/usr/bin/python
# -*- coding: UTF-8 -*-

if __name__ == '__main__':
    a = 234
    b = ~a
    print 'The a\'s 1 complement is %d' % b
    a = ~a
    print 'The a\'s 2 complement is %d' % a

The above example output is:

The a's 1 complement is -235
The a's 2 complement is -235

Python 100 Li