学习Python第二天

Posted 2022-06-01 zqntx

一、分支结构

if语句的使用

1、一元二次方程

x=float(input(‘x=‘))

if x>1:

      y=3*x-5

elif x>=-1:

        y=x+2

else:

        y=5*x+3

print (‘f(%.2f)=%.2f‘%(x,y))

2、计算器

num1,num2=map(float,input(‘Num1,Num2‘).split(‘,‘))

choose_method=input(‘Choose Method:[+,-,*,/])

if choose_method in ‘+_*/‘:

      pass

else:

      raise KeyError(‘Only choose [+,_,*,/]‘)

if choose_method == "+":

      print(‘%2f+%2f=%2f‘%(num1,num2,num1+num2))

elif choose_method =="-":

      print(‘%2f-%2f=%2f‘%(num1,num2,num1-num2))

elif choose_method =="*":

      print(‘%2f*%2f=%2f‘%(num1,num2,num1*num2))

elif choose_method =="/":

      print(‘%2f/%2f=%2f‘%(num1,num2,num1/num2))

3、简单石头布游戏

a=input(‘石头,剪刀,布‘)

import numpy as np

res=np.random.choice([‘石头‘,‘剪刀‘,‘布‘])

print(res)

if a == "石头" and res == ‘布‘:

      print(‘你输了‘)

elif a == "石头" and res == ‘剪刀‘:

      print(‘你赢了‘)

elif a == "布" and res == ‘石头‘:

      print(‘你赢了‘)

elif a == "布"and res == ‘剪刀‘:

      print(‘你输了‘)

elif a == "剪刀"and res == ‘布‘:

      print(‘你赢了‘)

elif a == "剪刀"and res == ‘石头‘:

      print(‘你输了‘)

4、构成三角形问题

import math

a = float(input(‘a = ‘))

b = float(input(‘b = ‘))

c = float(input(‘c = ‘))

if a+b>c and a+c>b and b+c>a:

      print (‘周长:%f‘%(a+b+c))

      p=(a+b+c)/2

      area=math.sqrt(p*(p-a)*(p-b)*(p-c))

      print(‘面积:%f‘%(area))

else:

      print (‘不能构成三角形‘)

5、银行卡密码

password=‘123‘

for i in range(3):

      i=input(‘输入一个密码‘)

      if i==password:

          print (‘登录成功‘)

          break

      else:

          print(‘密码错误‘)