''' Purpose: introduce the logical operators
'''

print()

print( '##### Logical values (bool)' )

print()

print( True )
print( False )

a = True
b = False

print(); input( 'Enter when ready: ' ); print()

print( '##### Logical and' )

print()

and1 = ( a and a )
and2 = ( a and b )
and3 = ( b and a )
and4 = ( b and b )

print( a, 'and', a, '=',  and1 )
print( a, 'and', b, '=',  and2 )
print( b, 'and', a, '=',  and3 )
print( b, 'and', b, '=',  and4 )

print(); input( 'Enter when ready: ' ); print()

print()

print( '##### Logical or' )
# true if one of a or b is true
print()

or1 = ( a or a )
or2 = ( a or b )
or3 = ( b or a )
or4 = ( b or b )

print( a, 'or', a, '=',  or1 )
print( a, 'or', b, '=',  or2 )
print( b, 'or', a, '=',  or3 )
print( b, 'or', b, '=',  or4 )

print(); input( 'Enter when ready: ' ); print()

print( '##### Logical negation' )

print()

negate1 = ( not a )
negate2 = ( not b )

print( 'not', a, '=',  negate1 )
print( 'not', b, '=',  negate2 )

print()