CSC111 Homework 9 Solutions
--D. Thiebaut 18:11, 14 April 2010 (UTC)
Problem 1
# hw9a.py
# Kristina Fedorenko
# (edited by D. Thiebaut)
# 111c - aq
#
#--- This program calculates how many people from a given list can
#--- fit into the elevator. Elevator's weight limit is set by
#--- the user. The program outputs the max number of people,
#--- their total weight and their names.
#
#--- prints a line of "-" ---
def line():
print "-"*40
#--- asks user for the weight limit. Rejects anything ---
#--- not within 0-1000 range ---
def getTotalWeight():
n = 1001
while not 0<=n<=1000:
try:
n = input("Please enter an elevator weight limit (0 - 1000): ")
if not 0<=n<=1000:
print "The number you entered is not within allowed range."
except SyntaxError:
print "Invalid input."
continue
except NameError:
print "Invalid input."
continue
return n
#--- MAIN FUNCTION ---
def main():
people = [ ("JT", 150), ("TJ", 80), ("TT", 120), ("BT", 170), ("Mike", 12),
("AF", 27), ("Lea", 78), ("Leo", 180), ("Al", 55), ("GK", 110),
("JR", 111), ("VB", 76)]
print
#--- get the limit from user ---
allowedWeight = getTotalWeight()
#--- sort people by weight ---
inElev = []
for name, weight in people:
inElev.append([weight, name])
inElev.sort()
#--- to fit max number of people, people with the lowest
#--- weight should be chosen
#--- weight all people and if more than limit, remove the heaviest ---
TotalWeight = 0
names = []
for weight, name in inElev: #--- recalculates weight
TotalWeight += weight
names.append( name )
if TotalWeight > allowedWeight:
TotalWeight -= weight
names.pop() #--- remove last name added
break
#--- prints out the results ---
line()
print "%-55s %-5d" %\
("Maximum number of people that can fit in the elevator:", len(names))
print
print "%-55s %-5d" %\
("Total weight of the people who fit in the elevator:", TotalWeight)
print
if len( names ) > 0:
print "Names of the people in the elevator:"
for name in names:
print " -", name
line()
print
main()
Problem 2
# hw9b.sol.py
# D. Thiebaut
# Computes e, the base of the natural log to 11 decimal
# places by summing up terms of the form 1/n!.
#
sum = 1.0
denom = 1
count = 1
print "-"*50
print "denom = ", denom
print "term = ", 0
print "sum = ", sum
print "count = ", count
# 71828182845
while sum*100000000000 < 271828182845:
print "-"*50
print "denom = ", denom
term = 1.0 / denom
print "term = ", term
sum = sum + term
print "sum = %1.20f" % sum
count += 1
denom = denom * count
print "count = ", count
print "final sum = %1.20f " % sum
print "count = ", count
# the output of the program is shown below:
"""
--------------------------------------------------
denom = 1
term = 0
sum = 1.0
count = 1
--------------------------------------------------
denom = 1
term = 1.0
sum = 2.00000000000000000000
count = 2
--------------------------------------------------
denom = 2
term = 0.5
sum = 2.50000000000000000000
count = 3
--------------------------------------------------
denom = 6
term = 0.166666666667
sum = 2.66666666666666651864
count = 4
--------------------------------------------------
denom = 24
term = 0.0416666666667
sum = 2.70833333333333303727
count = 5
--------------------------------------------------
denom = 120
term = 0.00833333333333
sum = 2.71666666666666634100
count = 6
--------------------------------------------------
denom = 720
term = 0.00138888888889
sum = 2.71805555555555544700
count = 7
--------------------------------------------------
denom = 5040
term = 0.000198412698413
sum = 2.71825396825396836675
count = 8
--------------------------------------------------
denom = 40320
term = 2.48015873016e-05
sum = 2.71827876984127003723
count = 9
--------------------------------------------------
denom = 362880
term = 2.7557319224e-06
sum = 2.71828152557319224769
count = 10
--------------------------------------------------
denom = 3628800
term = 2.7557319224e-07
sum = 2.71828180114638451315
count = 11
--------------------------------------------------
denom = 39916800
term = 2.50521083854e-08
sum = 2.71828182619849290091
count = 12
--------------------------------------------------
denom = 479001600
term = 2.08767569879e-09
sum = 2.71828182828616871092
count = 13
--------------------------------------------------
denom = 6227020800
term = 1.60590438368e-10
sum = 2.71828182844675936281
count = 14
--------------------------------------------------
denom = 87178291200
term = 1.14707455977e-11
sum = 2.71828182845823018710
count = 15
final sum = 2.71828182845823018710
count = 15
"""
Part 3, Optional and Extra Credit
# solution program for Hw9, Part 3 (optional and extra credit)
# D. Thiebaut
# The program reads a file formatted as follows:
#
# name Jane Moore
# semester fall 2010
# MWF 9 GEO 370
# TR 9 CSC 111
# MW 10 GOV 228
# MWF 13 DAN 113
# TR 13 FRN 254
# F 15 ESS 940
# F 14 ESS 940
#
# and outputs the same information into an html file, reformatted
# to look nice and organized.
#
def getFiles():
"""gets the name of files from the user"""
inputFile = outputFile = None
#--- ask for a valid file name ---
while True:
inputFile = raw_input( "Input file name? " )
try:
open( inputFile, 'r' )
break
except:
print "Invalid file name. Does not exit. Please reenter!"
#--- ask for an output file name with .htm or .html at the end ---
while True:
outputFile = raw_input( "Output file name? " )
if outputFile[-5:] != ".html" and outputFile[-4:] != ".htm":
print "Invalid file name. Make sure it ends in .htm or .html!"
else:
break
return inputFile, outputFile
def getInput( inputFile ):
"""reads the input file and returns the name, semester and
schedule lines to the calling program"""
lines = open( inputFile ).readlines()
name = lines[0].strip()
semester = lines[1].strip()
return name, semester, lines[2:]
def parse( lines ):
"""parses the schedule lines and returns 5 arrays containing
the various courses in the right slot"""
#--- create empty lists for each day of the week ---
M = []
T = []
W = []
R = []
F = []
#--- fill the arrays with which is a blank space in html ---
for i in range( 17 ): # index 8 corresponds to 8:00 am.
M.append( " " )
T.append( " " )
W.append( " " )
R.append( " " )
F.append( " " )
#--- read each line and extract information ---
for line in lines:
#print "line = ", line
words = line.split( )
#print "words = ", words
#--- skip badly formatted lines ---
if len( words ) != 4:
continue
#--- distribute courses in arrays for each day ---
Days, time, dept, num = words
time = int( time )
if Days.find( "M" )!= -1:
M[ time ] = dept+num
if Days.find( "T" )!= -1:
T[ time ] = dept+num
if Days.find( "W" )!= -1:
W[ time ] = dept+num
if Days.find( "R" )!= -1:
R[ time ] = dept+num
if Days.find( "F" )!= -1:
F[ time ] = dept+num
#print "M = ", M
return M, T, W, R, F
def generateHtml( outputFile, name, semester, M, T, W, R, F ):
"""Generate the html code and stores it into the output file"""
MM = TT = WW = RR = FF = ""
for i in range (8, 17): # index 8 is 8:00 a.m.
MM = MM + "<td>%s</td>" % M[i]
TT = TT + "<td>%s</td>" % T[i]
WW = WW + "<td>%s</td>" % W[i]
RR = RR + "<td>%s</td>" % R[i]
FF = FF + "<td>%s</td>" % F[i]
file = open( outputFile, 'w' )
file.write( """<html>
<title>%s's Schedule</title>
<body>
<h1>J%s's Schedule</h1>
<h2>%s<h2>
<table border="1">
<tr><td>Day</td><td>8:00</td><td>9:00</td><td>10:00</td><td>11:00</td>
<td>12:00</td><td>13:00</td><td>14:00</td><td>15:00</td><td>16:00</td></tr>
<tr><td>Monday</td>%s</tr>
<tr><td>Tuesday</td>%s</tr>
<tr><td>Wednesday</td>%s</tr>
<tr><td>Thursday</td>%s</tr>
<tr><td>Friday</td>%s</tr>
</table>
</body>
</html>
""" % ( name, name, semester, MM, TT, WW, RR, FF ) )
file.close()
# ---------------------------------------------------------------------------------
# MAIN PROGRAM
# ---------------------------------------------------------------------------------
def main():
# get file names from user
inputFile, outputFile = getFiles()
# parse information into fields.
name, semester, lines = getInput( inputFile )
# create lists for every day of the week
M, T, W, R, F = parse( lines )
# generate the html code
generateHtml( outputFile, name, semester, M, T, W, R, F )
main()
