CompSci 101 Test2 Sec1 Spring 2015

1. Note sets can be listed in any order
Lists of keys or values from dictionaries can be listed
in any order
To print a list, use [ ]'s
To print a set, use set( )

Output:
['b', 'e', 'e']
['b', 'e', 'e', 'h']
['a', 'b', 'c', 'j', 'k', 'p', 's']
set([1, 15])
set([1, 2, 3, 5, 8, 10, 11, 15])
set([3, 8, 11])
32
['H', 'C', 'U', 'D', 'F']
set([32, 25, 18, 12])
[10, 12, 25, 32]

2A. 
[14, 18]
['tennis', 'swimming']
['ketball', 'eball']

2B. 
firstlast = sorted([word[0] + word[-1] for word in shapes])

2C. 
whereisa = [(word,word.find('a')) for word in shapes if 'a' in word] 
 
OR
 
whereisa = [(word,word.find('a')) for word in shapes if word.find('a')>=0]

3A. 
def fileToList(datafile):
    newlist = []
    for line in datafile:
        line = line.strip()
        templist = line.split(":")
        alist = templist[0].split()  # split airline and flight number
        newlist.append([alist[0], alist[1], templist[1], int(templist[2])])
    return newlist

3B.
def largeFlights(datalist, size):
    answer = [] 
    for info in datalist: 
        if info[3]>= size: 
            answer.append(info[0]+'-'+info[1]+'-'+ info[2])
    return answer

OR

def largeFlights(datalist, size):
    answer = [] 
    for info in datalist: 
        if info[-1]>= size: 
            answer.append('-'.join(info[0:3])
    return answer

OR

def largeFlights(datalist, size): 
    return ['-'.join(info[0:3]) for info in datalist if info[3] >= size]

4A. 
def listOfOpponents(datalist):
    answerset = set([])
    for line in datalist:
        answerset.add(line[0])
    return sorted(list(answerset))

OR

return sorted(list(set( [line[0] for line in datalist] )))    

4B. 
def playersScoredLosingTeam(datalist):
    answerset= set([])
    for line in datalist:
        if line[3] == 'lost' and int(line[2]) <= 8:
            answerset.add(line[1]) 
    return list(answerset)

OR

def playersScoredLosingTeam(datalist):
    answerset= set([])
    for line in datalist:
        if line[-1] == 'lost':
            if int(line[2]) <= 8:
                answerset.add(line[1]) 
    return list(answerset)


4C. 
def teamsNotPlayed(datalist, league):
    setPlayed = set(listOfOpponents(datalist))
    setLeague = set(league)
    return sorted(list(setLeague - setPlayed))

OR

def teamsNotPlayed(datalist, league):
    answer = [ ]
    alist = listOfOpponents(datalist)
    for item in league:
        if item not in alist:
            answer.append(item)
    return answer


4D. 
def dictPlayerToGamesPlayedIn(datalist):
    d = {}
    for line in datalist:
        player = line[1]
        if player in d:
            d[player] += 1
        else:
            d[player] = 1
    return d

OR
 
# This solution uses a dictionary comprehension. Like a list comprehension, 
# you can build a dictionary with key-value pairs in one line.
def dictPlayerToGamesPlayedIn(datalist):
    d = {item[1]:0 for item in datalist }  # dictionary comprehension
                                           # initialize all keys to 0
    for item in datalist:
        d[item[1]] += 1
    return d 

4E. 
def dictPlayersToOpponentsBeat(datalist):
    d = {}
    for line in datalist:
        player = line[1]
        team = line[0]
        if line[3] == 'won':
            if player in d:
                d[player].append(team)
            else:
                d[player] = [team]
    return d

OR

# This solution uses a dictionary comprehension to put all the keys in with 
# an empty list. 
def dictPlayersToOpponentsBeat(datalist):
    d = {line[1]:[] for line in datalist if line[3]=='won'}
    for line in datalist:
        if line[3] == 'won':
            d[line[1]].append(line[0])
    return d

4F. 
def playerOnMostGamesWon(datalist):
    d = dictPlayersToOpponentsBeat(datalist)
    lenmax = max([len(d[key]) for key in d])
    for key in d:
        if len(d[key]) == lenmax:
            return key

OR

def playerOnMostGamesWon(datalist):
    d = dictPlayersToOpponentsBeat(datalist)   
    lenmax = 0
    keymax = ""
    for (key,value) in d.iteritems():
        if len(value) > lenmax:
            lenmax = len(value)
            maxkey = key
    return maxkey

OR

def playerOnMostGamesWon(datalist):
    d = dictPlayersToOpponentsBeat(datalist)   
    maxkeyval = ("", 0)
    for (key,value) in d.iteritems():
        if len(value) > maxkeyval[1]:
            maxkeyval = (key,len(value))
    return maxkeyval[0]