《Python语言程序设计 》第4章编程题答案（4）

wg19830119

4.21

from turtle import*

import math

x1,y1=eval(input('输入圆心的坐标：'))

x2,y2=eval(input('输入一个点的坐标：'))

radius=eval(input('输入圆半径：'))

penup()

goto(x1,y1-radius)

pendown()

circle(radius)

penup()

goto(x2,y2)

pendown()

dot(3,'red')

done()

distance=math.sqrt((x2-x1)**2+(y2-y1)**2)

if distance < radius:

print('point('+str(x2)+','+str(y2)+') is in thecircle')

else:

print('point('+str(x2)+','+str(y2)+') is not in thecircle')

4.22

from turtle import*

import math

x1,y1=eval(input('请输入圆心：'))

x2,y2=eval(input('请输入长和宽：'))

x3,y3=eval(input('输入一点的坐标：'))

penup()

goto(x1+x2/2,y1)

pendown()

left(90)

forward(y2/2)

left(90)

forward(x2)

left(90)

forward(y2)

left(90)

forward(x2)

left(90)

forward(y2/2)

penup()

goto(x3,y3)

pendown()

dot(3,'red')

done()

if ( abs(x3+x1)-abs(x1) <abs(x2)-abs(x1) ) and ( abs(y3+y1)-abs(y1) <abs(y2)-abs(y1) ):

print('point('+str(x3)+','+str(y3)+') is in therectangle ')

elif ( abs(x3+x1)-abs(x1) == abs(x2)-abs(x1) ) and ( abs(y3+y1)-abs(y1) <abs(y2)-abs(y1) ):

print('point('+str(x3)+','+str(y3)+') is on thewidth side ')

elif ( abs(x3+x1)-abs(x1) <abs(x2)-abs(x1) ) and ( abs(y3+y1)-abs(y1) == abs(y2)-abs(y1) ):

print('point('+str(x3)+','+str(y3)+') is on the lengthside ')

elif ( abs(x3+x1)-abs(x1) >abs(x2)-abs(x1) ) and ( abs(y3+y1)-abs(y1) >abs(y2)-abs(y1) ):

print('point('+str(x3)+','+str(y3)+') is out of therectangle ')

4.23:

import random

number=random.randint(1,13)

if number==1:

   number='A'

if number==11:

   number='J'

if number==12:

   number='Q'

if number==13:

   number='K'

color=random.randint(1,4)

if color==1:

   color='梅花'

if color==2:

   color='红桃'

if color==3:

   color='方块'

if color==4:

   color='黑桃'

print('the card you picked is '+color+str(number))

4.25:

x1,y1,x2,y2,x3,y3,x4,y4=eval(input('输入两条线段的四个点坐标:'))

if (( y1-y2 ) * ( x3-x4 ) - ( x1-x2 ) * ( y3-y4 ) ) != 0:

   x=( ( ( ( y1-y2 ) * x1 - ( x1-x2 )*y1 ) * ( x2-x4 ) )-( ( ( y3-y4 ) *x3-( x3-x4 ) * y3 ) * ( x1-x2 ) ) )/\

       ( ( y1-y2 ) * ( x3-x4 ) - (x1-x2 ) * ( y3-y4 ) )

   y=( ( ( ( y3-y4 ) * x3 - ( x3-x4 )*y3 ) * ( y1-y2 ) )-( ( ( y1-y2 ) *x1-( x1-x2 ) * y1 ) * ( y3-y4 ) ) )/\

       ( ( y1-y2 ) * ( x3-x4 ) - ( x1-x2 ) * ( y3-y4 ) )

print(x,y)

else:

print('eorro')

4.26:

number=eval(input('输入一个三位整数：'))

if99< number <1000 :

iftype(number) == type(1):        

       a=number // 100

       b=number % 10

if a==b :

print(str(number)+'is apalindrome')

else:

print(str(number)+'is not apalindrome')

else:

print('number is not int')

else:

print('input eorro')

4.27:

x,y=eval(input('输入一个点的坐标：'))

if  (0< x <200) and (y < (100-0.5*x)) :

print('the point is in the triangle')

else:

print('the point is not in the triangle')

4.28:

x1,y1,w1,h1=eval(input('输入第一个矩形的坐标以及宽和高：'))

x2,y2,w2,h2=eval(input('输入第二个矩形的坐标以及宽和高：'))

if (x1-(w1-w2)/2)<=x2<=(x1+(w1-w2)/2) and (y1-(h1-h2)/2)<=y2<=(y1+(h1-h2)/2):

print('r2 is insider1')

elif ((x1-(w1+w2)/2)<=x2<(x1-(w1-w2)/2) or (x1+(w1-w2)/2)<x2<=(x1+(w1+w2)/2)) and \

((y1-(h1+h2)/2)<=y2<(y1-(h1-h2)/2) or (y1+(h1-h2)/2)<y2<=(y1+(h1+h2)/2)):

print('r2 overlapsr1')

else:

print('r2 does notoverlap r1')

4.29:

import math

x1,y1,r1=eval(input('输入第一个圆的坐标以及半径：'))

x2,y2,r2=eval(input('输入第二个圆的坐标以及半径：'))

ifmath.sqrt((x1-x2)**2+(y1-y2)**2) <= abs(r1-r2):

print('circle2 isinside circle1')

elifabs(r1-r2)<math.sqrt((x1-x2)**2+(y1-y2)**2)<=r1+r2:

print('circle2overlaps circle1')

else:

print('circle2 doesnot overlaps circle1')

4.30:

import time

zone=eval(input('输入时区：'))

seconds=int(time.time())

second=seconds% 60

miniute=seconds// 60 % 60

hour=seconds //3600 % 24

if1<=hour<=12:

am_pm='am'

hour+=zone

print('the currenttime is '+str(hour)+':'+str(miniute)+':'+str(second)+am_pm)

else:

am_pm='pm'

hour=(hour+zone)% 12

print('the currenttime is '+str(hour)+':'+str(miniute)+':'+str(second)+am_pm)

4.31:

x0,y0,x1,y1=eval(input('输入起始点p0和终点p1坐标'))

x2,y2=eval(input('输入要判断的点p2的坐标'))

if (x1-x0)*(y2-y0)-(x2-x0)*(y1-y0)>0:

print('p2在线的左边')

elif (x1-x0)*(y2-y0)-(x2-x0)*(y1-y0)==0:

print('p2在线的右边')

else:

print('p2在同一条线上')

4.32:

x0,y0,x1,y1=eval(input('输入起始点p0和终点p1坐标'))

x2,y2=eval(input('输入要判断的点p2的坐标'))

if ((x1-x0)*(y2-y0)-(x2-x0)*(y1-y0))<0:

print('p2在线上')

else:

print('p2不在线上')

4.33:

number=eval(input('输入一个十进制整数：'))

number_ox=number % 16

if number <= 15:

if number_ox==10:

       number_ox='A'

elif number_ox==11:

       number_ox='B'

elif number_ox==12:

       number_ox='C'

elif number_ox==13:

       number_ox='D'

elif number_ox==14:

       number_ox='E'

elif number_ox==15:

       number_ox='F'

print(number_ox)

else:

print('invalid input')

4.34:

ox=input('输入一个十六进制字符：')

if ox == 'a' or ox=='A':

   print(10)

elif ox== 'b' or ox=='B':

   print(11)

elif ox== 'c' or ox=='C':

   print(12)

elif ox== 'd' or ox=='D':

   print(13)

elif ox== 'e' or ox=='E':

   print(14)

elif ox== 'f' or ox=='F':

   print(15)

elif 0 <= eval(ox) <= 9:

   print(eval(ox))

else:

   print('eorro')

4.35-4.39略，与之前题目相似，只是多了绘图过程

lmy0123

珍爱生命，果断回帖。

浅笑微凉

呵呵。。。

晚一会

LZ是天才，坚定完毕

oldpan

前排顶，很好！

zhape26

边撸边过

zhangyu

我也顶起出售广告位

zhxxuan

看起来好像不错的样子