Compsci 101 Exam 2 Sec01 Fall 2017

Problem 1 Sec 1

Part A: 
['K', 'B']
['K', 'B', ['P', 'Q']]
['H', 'M', 'Y', 'E', 'N']
['A', 'G', 'K']
['A', 'K']
[1, 2, 6]
[1, 2, 3, 6]
[1, 6]
set([9, 3, 6, 1])             # elements in any order is ok
set([1, 3, 6, 8, 9])          # elements in any order is ok 
set([8])                 
['A', 'J', 'M', 'Y']
['A', 'H', 'J', 'M', 'Y']
[2, 2, 5, 7, 7]
[('A', 2), ('H', 5), ('J', 2), ('M', 7), ('Y', 7)]

Part B:
[40, 20, 60, 30]              # elements in any order is ok
[2, 4, 2, 1]                  # elements in any order is ok
4

Problem 2 Sec 1

PartA:
['DUKE', 'NCSU', 'NCCU']

Part B:
['tm', 'eg', 'kf', 'na']


Part C:

result = [word+word for word in phrase.split() if len(word)%2 == 0]

ALT

result = [word*2 for word in phrase.split() if len(word)%2 == 0]

Part D:

def howMany(fruitlist):
    d = {}
    for item in fruitlist:
        [name, fruit] = item.split(":")
        if name not in d:
            d[name] = 0
        d[name] += 1
    return sorted(d.items())
    
Problem 3 Sec 1
Part A

def setup(filename):
    f = open(filename)
    ans = []
    for item in f:
        item = item.strip()
        alist = item.split(":")
        first = alist[:2]
        values = alist[2:]
        values = [int(num) for num in values]
        alist = first + values
        ans.append(alist)
    return ans

Part B:

def offersCompany(data, company):  
    ans = []
    for item in data:
        if company == item[0]:
            total = sum(item[2:])
            ans.append( (total, item[1]) )
    ans = sorted(ans)
    flip = [(t[1],t[0]) for t in ans]     # swap two items in each tuple
    return flip          

Problem 4 Sec 1
Part 4A: 

def students(data):
    ans = []
    for item in data:
        ans.append(item[1])
    return sorted(set(ans))

Part 4B: Sec 1

# unique clubs that have at least one student in year, year is a string
def clubsYear(data, year):
    ansset = set([])
    for item in data:
        club = item[0]
        year2 = item[2]
        if year2 == year:
            ansset.add(club)
    return sorted(ansset)

Part 4C: Sec 1
     
# return those students not in any club.
def studentsNotInClub(data,slist):   
    studs = set([])
    for item in data:
        studs.add(item[1])
    return sorted (set(slist) - studs) 

Part 4D: Sec 1

def dictClubsToMeetings(data):
    d = {}
    for item in data:
        club = item[0]
        person = item[1]
        meetings = int(item[3])
        if club not in d:
            d[club] = []
        d[club].append((person, meetings))       
    return d

Part 4E: Sec 1

# return the list of members from the club with the most minutes
def clubMostMeetings(data):
    maxnum = 0
    maxclub = ""
    maxlist = []
    d = dictClubsToMeetings(data)
    for (club,mlist) in d.items():
        x = sum([num for (person,num) in mlist])
        if x > maxnum:
            maxnum = x
            maxclub = club
            maxlist = [p for (p,num) in mlist ]
    return (maxclub, sorted(maxlist))   

Part 4F: Sec 1 

#return the name of the club with the most students
def clubMost(data):
    d = {}
    for item in data:
        club = item[0]
        stud = item[1]
        if club not in d:
            d[club] = 0
        d[club] += 1
    # find max
    maxclub = ""
    maxnum = 0
    for (club,num) in d.items():
        if num > maxnum:
            maxclub = club
            maxnum = num
    return maxclub