Test 1, Compsci 6, Fall 2010
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Problem 1
---
num = 13
d = 7.5
s = "please"

print num/2 = 6, integer division truncates in Python 2.6 (changes in 3.0)

print s[1:] = "lease"

print s[3] = 'a' (index starts at 0)

print num % 5 = 3, % is remainder, 13 = 2*5 + 3

print s*2 = "pleaseplease"

print (num-11)**3 = 8 since 13-11 = 2 and 2*2*2 = 8

Problem 2
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def sphereV(r):
    return 4.0/3*math.pi*(r**3)

def pyramid(levels):
    
    for n in range(1,levels+1):
        print '*' * n

def pyramid(levels):
    
    for n in range(1,levels+1):
        for i in range(0,n):
            print '*',
        print



def lastFirst(name):
 
    w = name.split(",")
    return w[1][1:] + " " + w[0]

# alternative

    index = name.find(",")
    return name[index+2:] + " " + name[:index]

def isPrime(n):

   for div in range(2,n):
       if n % div == 0:
           return False
   return True

# alternative for loop
   
   for div in range(2,int(math.sqrt(n))+2):

def domainCount(addrs,suffix):

    count = 0
    for email in addrs:
        if email.endswith(suffix):
            count += 1
    return count

def domainCount(addrs,suffix):

    return len([a for a in addrs if a.endswith(suffix)])


def makeAcronym(words):

    acro = ""
    for w in words:
        acros += w[0]

    return acro

def makeAcronym(words):

    ''.join([w[0] for w in words])



=============
Problem 3:

lists of size 2 cause denominator to be zero in both cases,
division b zero doesn't make sense mathematically, and for int
values causes an error (for float too).

the list is sorted so that low and high values occur first and last,
respectively, and slicing removes them

def computeScore(scores):

    low = min(scores)
    high = max(scores)
    lowc = scores.count(low)
    highc = scores.count(high)

    return (sum(scores)-low*lowc-high*highc)/(len(scores)-lowc-highc)


# alternative

def computeScore(scores):

    low = min(scores)
    high = max(scores)
    nlist = []
    for s in scores:
        if s != low and s != high:
            nlist.append(s)

    return sum(nlist)/len(nlist)


==============
Problem 5
==============

def getScore(filename,uname):

    file = open(filename)
    score = 0
    lineNum = 0
    for line in file:
        lineNum += 1
        parts = line.split(",")
        if parts[1] == uname:
            score += lineNum

    file.close()
    if score == 0:
        return "NO SCORE"
    return score

--
to score just top five, add scoreCount = 0 before loop,
increment scoreCount += 1 in if statement and change if
statement to guard:

      if parts[1] == uname and scoreCount < 5:


# first alternative

def getScore(filename,uname):

    file = open(filename)
    score = 0
    for i,line in enumerate(file):
        parts = line.split(",")
        if parts[1] == uname:
            score += (i+1)
    
# second alternative

def getScore(filename,uname):

    file = open(filename)
    score = 0
    nlist = []
    for line in file:
        nlist.append(line)

    for line in nlist:
        parts = line.split(",")
        if parts[1] == uname:
            score += nlist.index(line)+1