'''  Purpose: demonstrate arithmetic and use of variables
        for naming things
'''

# name some values
a = 13
b =  5

# We have variable identifiers and assign them values (a is the variable
# and 13 is the value!) so the computer sets aside memory to associate
# a to 13.
# Again notes will be posted so no need for rapid typing..

# I can use commas to print multiple things in a print statement!
# So it will print the string in the double/single quotes and then
# whatever is after the comma and each thing separated by a comma
# is separated by a space.

print( "a =", a )
print( "b =", b )

input()

# input() is waiting for user input! The user has to type something
# and hit enter before the program executes the next lines.
# display some integer calculations
print( 'Integer arithmetic' )

total        = a +  b
difference   = a -  b
product      = a *  b
dec_quotient = a /  b # Decimal division can yield a decimal!
int_quotient = a // b # Integer division will chop off everything after the whole number (chop off decimal)
remainder    = a %  b # So when it comes to remainder, think remainder
                      # after a division. 3%2 is 1 because there is
                      # a remainder of 1 when 3 is divided by 2.
power        = a ** b

# If you want to print more than one thing, separate them by commas!
# You can do this with different *types* more on this later so hang tight.
# Notice how we printed a string with a variable so it printed
# the string with the variable value.

# print() - everything inside the parenthesis is printed!
# Anything in double quotes is printed exactly as it says since
# it's a string. VARIABLES when printed print the value.
# print( 'a =', a) will print the string 'a =' with a space and the
# value of a which is 13. Console will say a = 13

print( a, "+", b, "=", total )

# Remember that if you wanna print a value print the variable/identifier.
print(  'a + b  =', total )
print( 'total =', total )
print(  'a - b  =', difference )
print(  'a * b  =', product )
print(  'a / b  =', dec_quotient )
print(  'a // b =', int_quotient )
print(  'a % b  =', remainder )
print(  'a ** b =', power )

input()

# introduce some other built-in functions
print( 'Some handy functions' )
c =  -10
d = 1.75
e = -1.75

print( "c =", c )
print( "d =", d )
print( "e =", e )

input()

# Important!! print(), abs(), float(), int() are built in functions!
# abs() gives back absolute value of whatever you pass into it.
# float() converts whatever you pass into it into a decimal number!
# A float is a decimal number.
# An int is an integer number.
# int() converts whatever you pass into it into an integer number.
# int chops off the decimal portion which is why 1.75 became 1 :)

abs_c = abs( c )
float_c = float( c )
int_d = int( d )

print( 'abs( c )   =',  abs_c )
print( 'float( c ) =', float_c )
print( 'int( d )   =', int_d )

print()