python 零起点(1)

第一个程序 输出hello world

1 #这是一个注释 
2 print "Hello world!"

数字和数学运算 + - * / % > <

1 #输入 'linuxroot 19'
2 print "linuxroot", 10 + 18 / 2
3 
4 #输出 False 19 比15大 
5 print 10 + 9 < 10 + 5
6 
7 #模运算 取余数 结果是 1
8 print 5 % 2

变量

 1 # 下面定义了一些变量
 2 
 3 my_age = 19
 4 
 5 my_name = 'linuxroot'
 6 
 7 my_work = 'student'
 8 
 9 # '\n'是进行换行输出
10 print "My age is: ",age,"\n"
11 print "and my name is:",name
12 
13 """变量名要以字母开头。"""
 1 my_age = 19
 2 my_name = 'linuxroot'
 3 my_work = 'student'
 4 
 5 print "My age is: %d " % my_age
 6 print "My name is: %s" % my_name
 7 
 8 #下面这句将输出 my work is: student
 9 print "My work is: %s" % my_work
10 
11 print "my age is: %d and my name is: %s" % (my_age,my_name)
12 #下面这句将输出 my work is: 'student'
13 print "my work is: %r" % my_work
14 
15 """%r 用来做 debug 比较好,因为它会显示变量的原始数据(raw data),而其它的符号则是用来向用户显示输出的。
16 """

打印

 1 #定义了一个my_print函数
 2 my_print = "%r %r %r %r"
 3 
 4 print my_print % (1, 2, 3, 4)
 5 print my_print % ("one", "two", "three", "four")
 6 print my_print % (True, False, True, False)
 7 print my_print % (my_print, my_print, my_print, my_print)
 8 
 9 days = "Mon Tue Wed Thu Fri Sat Sun"
10 months = "Jan\nFeb\nMar\nApr\nMay\nJun\nJul\nAug"
11 
12 print "Here are the days: ", days
13 print "Here are the moinths:", months
14 # 输出效果用上 只是用法不一样
15 print "Here are the days: %s" % days
16 print "Here are the moinths: %s" % months
17 
18 print """
19  三个双引号是为了书写多行输出
20 这是第三行
21 第四行
22 """ 

转义字符 

PS:需要的时候在去看看吧


 

原文地址:https://www.cnblogs.com/linuxroot/p/2775621.html