'''
    Purpose: introduction to dictionary'
'''

mappings = {}  # a dictionary! otherwise known as dict in Python
# {} is the empty dictionary
print( "Before:", mappings )
mappings[ 1 ] = 'odd'  # this is NOT indexing: the KEY is 1, and its VALUE is 'odd'
mappings[ 2 ] = 'even' # the KEY is 2, and its VALUE is 'even'
mappings[ 3 ] = 'odd' 
mappings[ 4 ] = 'even' 
mappings[ 5 ] = 'odd' 
mappings[ 6 ] = 'even' 
mappings[ 7 ] = 'odd' 
mappings[ 8 ] = 'even' 
mappings[ 9 ] = 'odd' 
mappings[ 'even' ] = 'a number is even if its remainder divided by 2 is 0'
mappings[ 'odd' ] = 'a number is odd if its remainder divided by 2 is 1'
print( "After:", mappings )
# dictionaries are UNORDERED; Python can order things in a dictionary however it likes
# even if this output is printed in the same order, don't count on it when you are doing programs with dicts
# dicts let us associate keys with values to solve problems

# numbers = []
# numbers[ 0 ] = 12  # not a valid line!
# print( numbers )

reply = input( 'Enter a number: ' )
n = int( reply )

status = mappings[ n ]

print( n, status )

reply = input( 'Enter even or odd: ' )

meaning = mappings[ reply ]

print( meaning )