CSC111 Homework 2 Solutions

Problem #1

# hw2a.py
# This program prompts the user to enter a number
# Then it will print out four different triangles
# with that number of lines of stars
#
# typical interaction with user:
# How many lines? 3
#
# triangle 1
#
# *
# **
# ***
#
# triangle 2
#
# ***
# **
# *
#
# triangle 3
#
#    *
#   **
#  ***
#
# triangle 4
#
#  ***
#   **
#    *
             
def main():
     #--------------------------------------
     # input from user for number of lines of stars
     # definitions for stars and spaces
     #-------------------------------------
     nolines = input ( " How many lines? " )
     stars = "*"
     space = " "
     print

     #---------------------------------------
     # triangle 1 output
     #--------------------------------------
     print "triangle 1"
     print
     for i in range (1, nolines+1):
         print i * stars
    
     #---------------------------------------
     # triangle 2 output
     #---------------------------------------
     print
     print "triangle 2"
     print
     for i in range (nolines):
         print (nolines-i)* stars
    
     #-------------------------------------
     # triangle 3 output
     #------------------------------------
     print
     print "triangle 3"
     print
     for i in range (1, nolines+1):
         print (nolines-i) * space,
         print i * stars
    
     #--------------------------------------
     # triangle 4 output
     #--------------------------------------
     print 
     print "triangle 4"
     print
     for i in range ( nolines):
         print i * space,
         print (nolines-i) * stars
            
main()

Problem #2

# hw2b.py
# Andrea Spain and Kate Zdepski 
# 111c-aw
# This program asks the user for three animals, paired with
# their respective noises. It then prints them in the lyrics to Old MacDonald.

def main():
    # Gets three animals and their noises from user.
    # Adds them to a list of the list.
    print "Welcome to old MacDonald's farm."
    print "Please enter three animals and the noise they make: "
    print ""
    farm = []
    for i in range(3):
         pair = [ raw_input( "animal? " ), raw_input( "noise? " ) ]
         farm.append(pair)
        
    # Separates the pair list into two variables and
    # prints them into the song using a loop.
    for pair in farm :
         animal, noise = pair
         print ""
         print "Old MacDonald had a farm, E-I-E-I-O"
         print "And on his farm he had some " + animal+ "s" + ", E-I-E-I-O"
         print "And a", noise, "here, and a", noise,
         print "there, everywhere a", noise + "!"
 
main()