CSC111 Homework 6 Solution 2014
--D. Thiebaut (talk) 09:46, 26 March 2014 (EDT)
There were several good solution programs for Homework 6. You were not required to use a main() function, although some did. The programs below were selected because they presented good features (not necessarily the same).
Program 1
The program below is a good example of how Python programs should be organized, with a header first, possibly a few import statements, maybe a constant or two, then a long list of function definitons (def statements), then the definition of the main() function, and at the very end, one call to main() that starts the whole program.
# Program: hw6a.py
# Programmer: Yumeng Wang(cf)
# (slightly edited by D. Thiebaut)
# The last edited time: 03/11/2014
# The program asks the user for an input which needs
# to be an integer that is greater or equal to 0,
# and then displays a chessboard with that dimension
# while each cell of the chessboard is represented by a
# 3*3 block.
# --------------------define functions---------------------
# printElement( visibility )- shows how to print one 1*3
# element in a 3*3 block.
def printElement( visibility ):
if visibility == True:
print( "###", end="" )
else:
print( "...", end="" )
# printOneLine( visibility )- print the first line of each row
def printOneLine( dimension, visibility ):
# it prints"###" and "..." one by one until
# the number of them is equal to the dimension
for i in range ( dimension ):
printElement( visibility )
visibility = not visibility
# when dimension is odd, change the visibility after
# it prints a line so that we have the original visibility
# at the beginning of every new line.
if dimension % 2 != 0:
visibility = not visibility
# printThreeLine( visibility )- print one row by print
# the same line three times.
def printThreeLine( dimension, visibility ):
for i in range (3):
printOneLine( dimension, visibility )
print()
# printBoard( visibility)- print the whole chessboard
# by printing the required number(dimension) of rows.
def printBoard( dimension, visibility ):
for i in range ( dimension ):
printThreeLine ( dimension, visibility )
visibility = not visibility
# ==================================================================
# MAIN PROGRAM
# ==================================================================
# main()- set the visibility to be true and print the
# printBoard( visibility ) function.
def main( ):
# get dimension from user
dimension = int(Input("Enter dimention of board: "))
while dimension < 0:
dimension = int(Input("Enter dimention of board: "))
printBoard( dimension, True )
main()
Program 2
This program gets points for good documentation and style.
# hw6a.py
# Thuy Nguyen (ce)
#
# This program asks the user for an integer that will represent
# a chessboard with that dimension. The chessboard uses a 3x3
# block to represent each cell of the board.
# For example, if user enters 3, this chessboard will be displayed:
# ###...###
# ###...###
# ###...###
# ...###...
# ...###...
# ...###...
# ###...###
# ###...###
# ###...###
# -----------------------------------------------------------------
# Makes either black (###) or white (...) segment
# for each cell
def printBlock( visible ):
if visible==True:
print( "###", end="" )
else:
print( "...", end="" )
# Makes indicated number of 3x3 cell(s) and alternates
# black (###) and white (...) cells for each row
def printLine( visibility, isOdd, dimension ):
for i in range( 3 ):
for i in range( dimension//2 ):
printBlock( visibility )
printBlock( not visibility )
if isOdd:
printBlock( visibility )
print()
# Alternates black (###) and white (...) cells the number of
# times that the user indicated for each column
def repeatLine( dimension, isOdd ):
for i in range( dimension//2 ):
printLine( True, isOdd, dimension )
printLine( False, isOdd, dimension )
if isOdd:
printLine( True, isOdd, dimension )
def main():
# Asks user for dimension of chessboard
dimension = int( Input( "Enter dimension of board: " ) )
# Asks user again for another input
# if user enters negative number
while dimension < 0:
dimension = int( Input( "Invalid input. Please enter 0 or positive number: " ) )
# Boolean variable when dimension is
# odd for the for loops in functions
isOdd = dimension % 2 == 1
# prints chessboard
repeatLine( dimension, isOdd )
main()
Program 3
This program was the shortest in the class. Very tight, concise, and works well. I prefer when the program contains more functions, but this one gets special reward for concise coding.
# Claire Dudek (ah)
# (slightly edited by D. Thiebaut)
# 3/9/2014
# Homework 6
# hw6a.py
# This program takes an input for the size of the grid
# and then outputs that grid using a 3x3 of # or . for
# each square in the grid
# Prints one row of the board. visible defines whether
# the row starts with white or black cell. Dim is the
# dimension of the board, controlling the # of cells on
# a row.
def printRow(visible, dim):
for i in range (dim):
if visible==True:
print("###", end="")
if visible == False:
print("...", end="")
visible = not visible
print()
# Prompts the user for a dimension, and then print the whole chessboard
# on the screen.
def main(visibility):
# Input from user - cannot be less than 0
dim = -1
while dim <= -1:
dim = int( input("Enter dimension of board: "))
for i in range (dim):
printRow(visibility, dim)
printRow(visibility, dim)
printRow(visibility, dim)
visibility = not visibility
# Makes the grid
main(True)
