python 字符串不支持修改
'''
a = [1,2,3,4]
a[1 : 3] = ['a','b']
a[1 : 3] = [2]
a[ : ] = []
print(a)
'''


'''
import copy
a = [[1,2],3,4]
#b = copy.copy(a) 浅拷贝
#b = a[:] 浅拷贝
b = copy.deepcopy(a) #深拷贝
#b = a 赋值引用
b[0][0] = 0
print(a)
print(b)
'''

// 下取整！
#!/usr/bin/python
# -*- coding: UTF-8 -*-
# 文件名：test.py

if True:
    print ("Answer")
    print ("True")
else:
    print ("Answer")
    # 没有严格缩进，在执行时会报错
  print ("False")
print(1,end = " "); //不换行输出！
print(r"yes\n", end = ""); 不转译，不换行输出！
print(r'"Genius is 1% inspiration and 99% perspiration."') //单双引号交替使用！
str = "hello world ";
print(2*str); 重复字符串！
str='123456789'
 
print(str)                 # 输出字符串
print(str[0:-1])           # 输出第一个到倒数第二个的所有字符
print(str[0])              # 输出字符串第一个字符
print(str[2:5])            # 输出从第三个开始到第五个的字符
print(str[2:])             # 输出从第三个开始后的所有字符
print(str[1:5:2])          # 输出从第二个开始到第五个且每隔一个的字符（步长为2）
print(str * 2)             # 输出字符串两次
print(str + '你好')         # 连接字符串
 
print('------------------------------')
 
print('hello\nrunoob')      # 使用反斜杠(\)+n转义特殊字符
print(r'hello\nrunoob')     # 在字符串前面添加一个 r，表示原始字符串，不会发生转义
height = float(input("输入身高（米）："))
weight = float(input("输入体重（千克）："))
bmi = weight / (height * height)  #计算BMI指数
if bmi<18.5:
    print("BMI指数为："+str(bmi))
    print("体重过轻")
elif bmi>=18.5 and bmi<24.9:
    print("BMI指数为："+str(bmi))
    print("正常范围，注意保持")
elif bmi>=24.9 and bmi<29.9:
    print("BMI指数为："+str(bmi))
    print("体重过重")
else:
    print("BMI指数为："+str(bmi))
    print("肥胖")
print ("我叫 %s 今年 %d 岁!" % ('小明', 10))
var = 1
while var == 1:  # 表达式永远为 true
    num = int(input("输入一个数字  :"))
    print("你输入的数字是: ", num)
    var = False
print("Good bye!")
languages = ["C", "C++", "Perl", "Python"]
for x in languages:
    print (x)
sites = ["Baidu", "Google","Runoob","Taobao"]
for site in sites:
    if site == "Runoob":
        print("菜鸟教程!")
        break
    print("循环数据 " + site)
else:
    print("没有循环数据!")
print("完成循环!")
f = False
for i in range(1,10,1): #不包括10；
    if(i == 10):
        f = True
if(f == True):
    print("YES")
else:
    print("NO")
for letter in 'Runoob':
    if letter == 'o':
        pass
        print('执行 pass 块')
    print('当前字母 :', letter)

print("Good bye!")

输入的两种方式！

a,b=map(int,input().split())
print(a%b)

a,b = input().split()
a = int(a); b = int(b);
print(a%b)
//单个输入两种写法！
a = int(input())
print(a)
a = input().split()
a = int(a[0])
print(a)
s = "hello world"
for i in s:
    print(chr(ord(i)+1),end = "")

多组输入

while True:
    try:
        a,b = map(int,input().split())
        print(a+b)
    except:
        break


python 中字符串不可修改！
s = str(input())
print(len(s.replace(" ","")))

格式化字符串

a,b,c = map(float,input().split())
ans = (a+b+c)
print("%.2f %.2f"%(ans,ans/3))
a,b = input().split()
  
a = float(a)
b = float(b)

print("{:.3f}%".format(b/a*100))
//输出16进制数字！
a,b = map(int,input().split())
c = a+b
print("%x" %c)

倒序输出字符串！

a = input();
print(a[::-1])

st = str(input())
for i in range(len(st)-1,-1,-1):
    print(st[i],end = "")

import

import math
a,b,c = map(float,input().split())
p = (a+b+c)/2
print("circumference=%.2f area=%.2f" %(a+b+c,math.sqrt(p*(p-a)*(p-b)*(p-c))))

列表

a = list(map(int,input().split()))
a.sort()
print(abs(a[3]+a[0] - a[2]-a[1]))
a = list(map(int,input().split()))
print(max(a))

元组

a = ('1',2,3)
元组不能修改

字典

aa

集合

aa

获取字符串数值

//直接转换为int即可！
s = str(input())
yue = int(s[4]+s[5])
if (yue >= 3 and yue <= 5):
    print ("spring")
if (yue >= 6 and yue <= 8):
    print ("summer")
if (yue >= 9 and yue <= 11):
    print ("autumn")
if (yue >= 1 and yue <= 2 or yue == 12):
    print ("winter")

判断是哪一种字符

s = "13/"
for i in s:
    if i.isdigit():
        print(i)
    elif i.isalpha():
        print(i)
    else:
        print(i)

主函数

if __name__ == "__main__":
    n = int(input())
    for i in range(1,n+1,1):
        ok = True
        if i % 4 == 0:
            ok = False
        s = str(i)
        for c in s:
            if c == '4':
                ok = False
        if ok == True:
            print(i)
fi:
n = int(input())
def solve(n):
    if n == 1 or n == 2:
        return 1
    return solve(n-1) + solve(n-2)
if __name__ == "__main__":
    print(solve(n))