第五章-数字课后答案

5-1

普通整型和长整型能表示的数据的位数不同。用大写字母"L"加在后面表示长整型，目前整型和长整型正在逐渐缓慢的统一。

5-2

(a)

def plus(a, b):
    return a*b;

(b)

>>>plus(4, 5)
20

5-3

 1 def scoreOut(x):
 2     scoreDic = {9:"A",8:"B",7:"C",6:"D"}
 3     score  = x / 10
 4     for item in sorted(scoreDic.keys(),reverse = True):
 5         if score >= item:
 6             out = scoreDic[item]
 7             break
 8         else:
 9             out = "F"
10     return out
11 
12 score = input("Enter your number,Please!")
13 print "Your level is: %s" % scoreOut(score)

5-4

1 def leap_year(n):
2     if (n % 4==0 and n % 100!=0) or n % 400==0:
3         return "is";
4     else:
5         return "is not";
6 
7 year = input("Please input the year: ");
8 print "Year %d %s a leap year!" % (year, leap_year(year))

5-5

 1 def cal_money(x):
 2     cent_25 = x/25
 3     cent_10 = (x - 25 * cent_25)/10
 4     cent_5 = (x - 25 * cent_25 - 10 * cent_10)/5
 5     cent_1 = x - 25 * cent_25 - 10 * cent_10 - 5 * cent_5
 6     return cent_25,cent_10,cent_5,cent_1
 7 
 8 cent = input("input your cent,please: ")
 9 a, b, c, d = cal_money(cent)
10 print "%d convert to %d 25cent, %d 10cent, %d 5cent, %d 1cent" % (cent, a, b, c, d)

5-6

 1 def calculate(str):
 2     sList = str.split(" ")
 3     if sList[1] == "+":
 4         return int(sList[0])+int(sList[2])
 5     elif sList[1] == "-":
 6         return int(sList[0])-int(sList[2])
 7     elif sList[1] == "*":
 8         return int(sList[0])*int(sList[2])
 9     elif sList[1] == "/":
10         return int(sList[0])/int(sList[2])
11     elif sList[1] == "%":
12         return int(sList[0])%int(sList[2])
13     elif sList[1] == "**":
14         return int(sList[0])**int(sList[2])
15     else:
16         return "error operator"
17 
18 while True:
19     strEval = raw_input("please input the eval(q to quit): ")
20     if strEval.lower() == "q":
21         break
22     print "the result is %d" % (calculate(strEval))

5-8

 1 def square(x):
 2     return x*x
 3 
 4 def cube(x):
 5     return x*x*x
 6 
 7 import math
 8 def circle(x):
 9     return math.pi * x * x
10 
11 def ball(x):
12     return 4.0/3 * math.pi * r * r * r

5-9

(a)因为017等数字代表的是八进制数字

(b)56和78后面的是字母l，不是数字1，表示的是长整型

5-10

1 def temperature(x):
2     return (x - 32) * (5.0/9.0)
3 
4 if __name__ == "__main__":
5     strTem = input("input the temperature,please: ")
6     print "the result is: %f" % temperature(strTem)

5-11

(a)

1 def odd():
2     aList = []
3     for i in range(21):
4         if i%2 == 0:
5             aList.append(i)
6     return aList

(b)

1 def even():
2     aList = []
3     for i in range(21):
4         if i%2 == 1:
5             aList.append(i)
6     return aList

(c)

取余

(d)

1 def calculate():
2     number_a = input("Please input a integer: ")
3     number_b = input("Please input another integer: ")
4     if number_a % number_b == 0 or number_b % number_a == 0:
5         return True
6     else:
7         return False

5-12

1 import sys;     #加载sys模块
2 
3 #整数的范围，超过则自动转换为长整数
4 print (sys.maxint);
5 print(-sys.maxint-1);
6 
7 #浮点数的范围
8 print(sys.float_info);
9 print(sys.long_info);

5-13

1 def translate():
2     time_str = raw_input("Please input the time, like 14:15:
")
3     sList = time_str.split(":")
4     if 0<=int(sList[0])<=24 and 0<=int(sList[1])<=60:
5         time = int(sList[0]) * 60 + int(sList[1])
6         return time
7     else:
8         return "error time!"

5-15

1 def GCM(num1, num2):
2     tempNum = abs(num1 - num2)
3     if (num1 % tempNum) == (num2 % tempNum) == 0:
4         return tempNum
5     else:
6         return GCM(num2, tempNum)
7 def LCM(num1, num2):
8     tempNum = GCM(num1, num2)
9     return num1 * num2 / tempNum

5-17

 1 import random
 2 while 1:  
 3     N1=random.randint(2,100)  
 4     N2=random.randint(1,100)  
 5     if N1>N2:  
 6         break  
 7 print 'N1 is %d, N2 is %d' %(N1,N2)   
 8 list1=[]  
 9 for i in range(0,N1):  
10     n=random.randint(0,2**31-1)  
11     list1.append(n)      
12 print list1  
13 list2=random.sample(list1,N2)  
14 list2.sort()  
15 print list2

第五章-数字 课后答案

第五章-数字课后答案