python核心编程 第五章练习题答案（简单的没上）

#习题5-5
while True:
usr = int(eval(raw_input('Enter your $cents: ').strip()))
while usr in range(0,101):
break
else:
print 'OverIndex~!'
usr = int(eval(raw_input('Enter your $cents: ').strip()))
re25 = usr%25
if re25 == 0:
print "needs '%i' 25cent  coins" % (usr/25,)
elif re25%10 == 0:
print "needs '%i' 25cent  and '%i' 10cent  coins" % ((usr-re25)/25,(re25)/10)
elif (re25%10)%5 == 0:
print "needs '%i' 25cent and '%i' 10cent  and '%i' 5cent  coins" %  \
((usr-re25)/25,(re25-(re25%10))/10,(re25%10)/5)
else:
print "needs '%i' 25cent  and '%i' 10cent  and '%i' 5cent  and '%i' 1cent coins" %  \
((usr-re25)/25,(re25-(re25%10))/10,(re25%10-(re25%10)%5)/5,(re25%10)%5)
#习题5-6
<pre name="code" class="python">import operator
'''
the module enables users to input an expression,then it will gives the result
of the expression as recognized the operator and operands
'''
usript = raw_input('enter an expression(int type only!): ').strip()
operators = {'+':operator.add,'-':operator.sub,'/':operator.truediv,'%':operator.mod,'**':operator.pow,'*':operator.mul}
newls = []
for ops in operators.keys():
if '**' in usript:
ops = '**'
if ops in usript:
newls.append(ops)
usr = usript.split(ops)
for i in usr:
i.strip()
newls.append(int(i))
break
try:
result = operators[ops](newls[1],newls[2])
except ZeroDivisionError,e:
print 'Error occurs: ',e
else:
print 'the result is:',result

#! usr/bin/env python
arg1,arg2 =raw_input("enter two nums to find their max common divisor:  ").strip().split(",")
arg1 = int(arg1)
arg2 = int(arg2)
def maxcomdiv(num1,num2):
'''this function can find the max common divisor of two numbers(int only)'''
maxn = max(num1,num2)
minn = min(num1,num2)
try:
if  maxn%minn == 0:
print 'the max common divisor:',minn
return minn
else:
maxcomdiv(minn,maxn-minn)
except ZeroDivisionError,e:
print 'Error occurs:', e

def mincomul(num1,num2):
'''this function can find the max common multiple of two numbers(int only)'''
maxn = max(num1,num2)
minn = min(num1,num2)
if not maxn%minn:
comul = maxn
elif maxcomdiv(maxn,minn) == 1:
comul = maxn*minn
else:
i = 2
while True:
if not (maxn*i)%minn:
comul = maxn*i
break
else:
i+=1
print 'the minimal common multiple is:',comul
if __name__=='__main__':
maxcomdiv(arg1,arg2)
mincomul(arg1,arg2)
#5-16
menu = "Pymt#\tPaid\t\tAmount Remaining Balance\n-----\t------\t\t----------"
openb = eval(raw_input('Enter opening balance: ').strip())
monp = eval(raw_input('Enter monthly payment: ').strip())
print menu
paid = 0.00
for i in xrange(0,1000000):
    print i,'\t$',paid,'\t\t$',openb
    if paid == 0.00:
        paid = monp  
    if openb<monp:
        paid = openb
    if openb == 0.00:
        break
    openb-=paid

#5-17
import random
lists=[]
for i in range(0,random.randrange(0,101)):
    n = random.randrange(0,2**31)
    lists.append(n)  
while True:
    try:
        newlist =[]
        for i in range(0,random.randrange(0,101)):
            newlist.append(lists[i])
        print newlist
        break
    except IndexError , e:
        print 'Error occurs:',e