python的输入输出
radius = eval(input("输入半径")) //输入的值是一个字符串，用eval()转换为一个数值
area = radius * radius * 3.14159
print("这个半径为",radius,"圆的面积为",area)
PYthon中的变量不用声明
Python的解释器不能确认在多行中哪里是语句的结尾，你可以在一行的结尾处放置 ‘’ 符号，告诉解释器继续到下一行。如：
radius = eval(input("输入半径")) #输入的值是一个字符串，用eval()转换为一个数值
area = radius * radius * #没有符号，就会报错。
3.14159
print("这个半径为",radius,"圆的面积为",
area) #这个因为有括号,不会报错。
/、//、%和*、**各自区别
在控制台分别输入以下运算。
类型转换和四舍五入
round只能四舍五入为最近的整数。
int（）取整。
如何保存小数点后两（n）位？并不能四舍五入的保存两位小数。
floatNum = eval(input("请输入至少有三位小数的值："))
print("保留小数点后两位：",int(floatNum*100)/100.0)
显示GMT时间
import time
currentTime = time.time()
totalSeconds = int(currentTime)
currentSeconds = totalSeconds%60
totalMinutes = totalSeconds//60
currentMinutes = totalMinutes%60
totalHours = totalMinutes//60
currentHours = totalHours%24
print("Current time is",currentHours,":",currentMinutes,":",currentSeconds)
turtle的基本图形
# -*- coding: utf-8 -*-
"""
Created on Tue Mar 8 09:57:32 2022
@author: Ricardo
"""
#2.1
'''c = eval(input("请输入摄氏度："))
f = (9/5)*c +32
print(c,"C等于",f,"F")
#2.2
radius = eval(input("输入圆的半径："))
high = eval(input("输入圆柱的高："))
area = radius * radius *3.14159
volume = area *high
print("圆柱的体积：",volume)
#
num = eval(input("请输入1~1000中任意一个数："))
thousand = num//1000
hundred = (num%1000)//100
ten = (num%100)//10
one = num%10
print("各位数字之和为",thousand+hundred+ten+one)
#
minutes = eval(input("输入分钟数："))
totalDays = minutes//(24*60)
years = totalDays//365
days = totalDays%365
print("一共",years,"年，",days,"天。")
#
import turtle
radius = eval(input("输入半径："))
turtle.color("red")
turtle.penup()
turtle.goto(radius,radius)
turtle.pendown()
turtle.circle(radius)
#
turtle.color("red")
turtle.penup()
turtle.goto(radius,-radius)
turtle.pendown()
turtle.circle(radius)
#
turtle.color("red")
turtle.penup()
turtle.goto(-radius,-radius)
turtle.pendown()
turtle.circle(radius)
#
turtle.color("red")
turtle.penup()
turtle.goto(-radius,radius)
turtle.pendown()
turtle.circle(radius)
turtle.done()
#
import turtle
turtle.forward(50)
turtle.left(45)
turtle.forward(50)
turtle.left(45)
turtle.forward(50)
turtle.left(45)
turtle.forward(50)
turtle.left(45)
turtle.forward(50)
turtle.left(45)
turtle.forward(50)
turtle.left(45)
turtle.forward(50)
turtle.left(45)
turtle.forward(50)
turtle.done()
#
import turtle
turtle.forward(100)
turtle.left(135)
turtle.forward(100)
turtle.left(135)
turtle.forward(100)
turtle.left(135)
turtle.forward(100)
turtle.left(135)
turtle.forward(100)
turtle.left(135)
turtle.forward(100)
turtle.left(135)
turtle.forward(100)
turtle.left(135)
turtle.forward(100)
turtle.left(135)
turtle.done()
#
import turtle
turtle.color("blue")
turtle.forward(100)
turtle.left(45)
turtle.forward(50)
turtle.backward(50)
turtle.left(45)
turtle.forward(50)
turtle.right(45)
turtle.forward(50)
turtle.backward(50)
turtle.left(135)
turtle.forward(100)
turtle.right(135)
turtle.forward(50)
turtle.backward(50)
turtle.right(135)
turtle.forward(50)
turtle.left(135)
turtle.forward(50)
turtle.right(45)
turtle.forward(100)
turtle.left(90)
turtle.forward(50)
turtle.left(90)
turtle.forward(100)
turtle.left(90)
turtle.forward(50)
turtle.done()
'''
