ex01简单print语句

#-*- coding:utf-8-*-
print "hello world"
print "Hello again"
print "i like typing this"
print "this is fun"
print 'yap printing.'
print "i'd much rather you 'not’."
print 'I "said" do not touch this.'

ex02注释

# A comment, this is so you can read your program later.  
# Anything after the # is ignored by python.  
  
print "i could have code like this." # and the comment after is ignored  
  
# You can also use a comment to "disable" or comment out a piece of code:  
# print "This won't run."  
  
print "This will run." 

ex03运算符，浮点数

print "I will now count my chicken:"  
  
  
print "Hens", 25 + 30 / 6  
print "Roosters", 100 - 25 * 3 % 4  
  
  
print "Now i will count the eggs:"  
  
  
print 3 + 2 + 1 - 5 + 4 % 2 -1 / 4 + 6  
  
  
print "Is it true 3 + 2 < 5 - 7?"  
  
  
print 3 + 2 < 5 - 7  
  
  
print "What is 3 + 2?", 3 + 2  
print "What is 5 - 7", 5 - 7  
  
  
print "Oh, that's why it's False."  
  
  
print "How about some more."  
  
  
print "Is it greater?", 5 >= -2  
print "Is it less or equal?", 5 <= -2  
  
  
print "----------------------------------"   
  
  
print "I will now count my chicken:"  
  
  
print "Hens", 25.0 + 30.0 / 6.0  
print "Roosters", 100.0 - 25.0 * 3.0 % 4.0  
  
  
print "Now i will count the eggs:"  
  
  
print 3.0 + 2.0 + 1.0 - 5.0 + 4.0 % 2.0 - 1.0 / 4.0 + 6.0  
  
  
print "Is it true 3 + 2 < 5 - 7?"  
  
  
print 3.0 + 2.0 < 5.0 - 7.0  
  
  
print "What is 3.0 + 2.0?", 3.0 + 2.0  
print "What is 5.0 - 7.0", 5.0 - 7.0  
  
  
print "Oh, that's why it's False."  
  
  
print "How about some more."  
  
  
print "Is it greater?", 5.0 >= -2.0  
print "Is it less or equal?", 5.0 <= -2.0  

ex04使用变量

cars = 100  
space_in_a_car = 4.0  
drivers = 30  
passengers = 90  
cars_not_driven = cars - drivers  
cars_driven = drivers  
carpool_capacity = cars_driven * space_in_a_car  
average_passengers_per_car = passengers / cars_driven  
  
  
print "There are", cars, "cars available."  
print "There are only", drivers, "drivers available."  
print "There will be", cars_not_driven, "empty cars today."  
print "We can transport", carpool_capacity, "people today."  
print "We have", passengers, "to carpool today."  
print "We need to put about", average_passengers_per_car, "in each car." 

ex05格式化字符串

my_name = 'Gao'  
my_age = 31 # not a lie  
my_height = 174 # cm  
my_weight = 80 # kg  
my_eyes = 'Black'  
my_teeth = 'White'  
my_hair = 'Black'  
  
print "Let's talk about %s." % my_name  
print "He's %d cm tall." % my_height  
print "He's %d kg heavy." % my_weight  
print "Actually that's not too heavy."  
print "He's got %s eyes and %s hair." % (my_eyes, my_hair)  
print "His teeth are usually %s depending on the coffee." % my_teeth  
  
# this line is tricky, try to get it exactly right  
print "If I add %d, %d, and %d I get %d." % (  
    my_age, my_height, my_weight, my_age + my_height + my_weight)  

ex06格式化字符串，多行文本

x = "There are %d types of people." % 10  
binary = "binary"  
do_not = "don't"  
y = "Those who know %s and those who %s." % (binary, do_not)  
  
print x  
print y  
  
print "I said: %r." % x  
print "I also said: '%s'." % y  
  
hilarious = False  
joke_evaluation = "Isn't that joke so funny?! %r"  
  
print joke_evaluation % hilarious  
  
w = "This is the left side of..."  
e = "a string with a right side."  
  
print w + e  

ex07字符串连接

print "Mary had a little lamb."  
print "Its fleece was white as %s." % 'snow'  
print "And everywhere that Mary went."  
print "." * 10 #what's that do?  
  
end1 = "C"  
end2 = "h"  
end3 = "e"  
end4 = "e"  
end5 = "s"  
end6 = "e"  
end7 = "B"  
end8 = "u"  
end9 = "r"  
end10 = "g"  
end11 = "e"  
end12 = "r"  
  
# watch that comma at end. try removing it to see what happens  
print end1 + end2 + end3 + end4 + end5 + end6,  
print end7 + end8 + end9 + end10 + end11+ end12   

ex08格式化字符串

formatter = "%r %r %r %r"  
  
print formatter % (1, 2, 3, 4)  
print formatter % ("one", "two", "three", "four")  
print formatter % (True, False, False, True)  
print formatter % (formatter, formatter, formatter, formatter)  
print formatter % (  
    "I had this thing.",  
    "That you could type up right.",  
    "But it didn't sing.",  
    "So I said goodnight."  
)  

ex09换行符，打印多行字符

# Here's some new stange stuff, remember type it exactly.  
  
days = "Mon Tue Wed Thu Fri Sat Sun"  
months = "Jan\nFeb\nMar\nApr\nMay\nJun\nJul\nAug"  
  
print "Here are the days: ", days  
print "Here are the months: ", months  
  
print """ 
There's something going on here. 
With the three double-quotes. 
We'll be able to type as much as we like. 
Even 4 lines if we want, or 5, or 6. 
"""  

ex10转义字符

# coding: utf-8  
# 转义字符 escape sequence  
tabby_cat = "\tI'm tabbed in."  
persian_cat = "I'm split\non a line."  
backslash_cat = "I'm \\a \\ cat."  
  
fat_cat = """ 
I'll do a list: 
\t* Cat food 
\t* Fishies 
\t* Catnip\n\t* Grass 
"""  
  
print tabby_cat  
print persian_cat  
print backslash_cat  
print fat_cat  

转义字符
\ 反斜杠（、）
' 单引号（‘）
" 双引号（“）
\a ASCII 响铃符（BEL）
\b ASCII 退格符（BS）
\f ASCII 进纸符 （FF）
\n ASCII 换行符 （LF）
\N{name} Unicode [数据库]中的字符名，其中name是它的名字，仅适用于Unicode
\r ASCII 回车符 (CR)
\t ASCII 水平制表符
\uxxxx 值为16位十六进制值xxxx的字符（仅适用于Unicode）
\Uxxxxxxxx 值为32位十六进制值xxxxxxxx的字符（仅适用于Unicode）
\v ASCII 垂直制表符 （VT）
\ooo 值为八进制值ooo的字符
\xhh 值为十六进制数hh的字符

#打印出风车转得效果  
while True:  
    for i in ["/","-","|","\\","|"]:  
        print "%s\r" % i,  

ex11输入

print "How old are you?"  
age = raw_input()  
print "How tall are you?"
height = raw_input()  
print "How much do you weigh?"  
weight = raw_input()  
  
  
print "So, you're %r old, %r tall and %r heavy." %(  
    age,height,weight)  
print "So, you're %s old, %s tall and %s heavy." %(  
    age,height,weight)  

ex12提示输入

age = raw_input("How old are you? ")  
height = raw_input("How tall are you? ")  
weight = raw_input("How much do you weigh? ")  
  
print "So, you're %r old, %r tall and %r heavy." %(  
    age, height, weight)  
print "So, you're %s old, %s tall and %s heavy." %(  
    age, height, weight)  

ex13参数传递

from sys import argv  
  
script, first, second, third = argv  
  
print "The script is called:", script  
print "Your first variable is:", first  
print "Your second variable is:", second  
print "Your third variable is:", third  

ex14argv参数传值

from sys import argv  
  
script, user_name = argv  
prompt = '>'  
  
print "Hi %s, I'm the %s script." % (user_name, script)  
print "I'd like to ask you a few questions."  
print "Do you like me %s?" % user_name  
likes = raw_input (prompt)  
  
print "Where do you live %s?" % user_name  
lives = raw_input(prompt)  
  
print "What kind of computer do you have?"  
computer = raw_input (prompt)  
  
print """ 
Alright, so you said %r about liking me. 
You live in %r. Not sure where that is. 
And you have a %r computer.  Nice. 
""" % (likes, lives, computer)  

ex15打开文件

from sys import argv  
  
script, filename = argv  
  
txt = open(filename)  
  
print "Here's your file %r:" % filename  
print txt.read()  

from sys import argv  
  
script, filename = argv  
  
txt = open(filename)  
  
print "Here's your file %r:" % filename  
print txt.read()  

txt.close()  
  
print "Type the filename again:"  
file_again = raw_input("> ")  
  
txt_again = open(file_again)  
  
print txt_again.read()  
txt_again.close()  

ex16读写文件

# coding:utf-8  
#方法1  
''''' 
from sys import argv 
 
script, filename = argv 
 
print "We're going to erase %r." % filename 
print "If you don't want that, hit CTRL-C(^C)." 
print "If you do want that, hit RETURN." 
 
raw_input("?") 
 
print "Opening the file..." 
target = open (filename, 'w') 
 
print "Truncating the file. Goodby!" 
target.truncate() 
 
print "Now I'm going to ask you for three lines." 
 
line1 = raw_input("line 1: ") 
line2 = raw_input("line 2: ") 
line3 = raw_input("line 3: ") 
 
print "I'm going to write these to the file." 
 
target.write(line1) 
target.write("\n") 
target.write(line2) 
target.write("\n") 
target.write(line3) 
target.write("\n") 
 
print "And finally, we close it." 
target.close() 
'''  
#方法2  
from sys import argv  
  
script, filename = argv  
  
print "We're going to erase %r." % filename  
print "If you don't want that, hit CTRL-C(^C)."  
print "If you do want that, hit RETURN."  
  
raw_input("?")  
  
print "Opening the file..."  
target = open (filename, 'w')  
  
print "Truncating the file. Goodby!"  
target.truncate()  
  
print "Now I'm going to ask you for three lines."  
  
line1 = raw_input("line 1: ")  
line2 = raw_input("line 2: ")  
line3 = raw_input("line 3: ")  
  
print "I'm going to write these to the file."  
  
target.write(line1 + "\n" + line2 + "\n" + line3 + "\n")  
  
print "And finally, we close it."  
target.close()  

ex17文件复制

from sys import argv  
from os.path import exists  
  
script, from_file, to_file = argv  
  
print "Copying from %s to %s " % (from_file, to_file)  
  
# we could do these two on one line too, how?  
in_file = open(from_file)  
indata = in_file.read()  
  
print "The input file is %d bytes long" % len(indata)  
  
print "Does the output file exist? %r" % exists(to_file)  
print "Ready, hit RETURN to continue, CTRL-C to abort."  
raw_input()  
  
out_file = open(to_file, 'w')  
out_file.write(indata)  
  
print "Alright, all done."  
  
out_file.close()  
in_file.close() 

ex18命名变量代码函数

# this one is like your scripts with argv  
def print_two(*args):  
    arg1, arg2 = args  
    print "arg1: %r ,arg2: %r" % (arg1, arg2)  
  
# ok, that *args is actually pointless, we can just do this  
def print_two_again(arg1, arg2):  
    print "arg1: %r, arg2: %r" % (arg1, arg2)  
  
# this just takes one argument  
def print_one(arg1):  
    print "arg1: %r" % arg1  
      
# this one takes no arguments  
def print_none():  
    print "I got nothing."  
      
print_two("Z","W")  
print_two_again("Z","W")  
print_one("First!")  
print_none()  

ex19函数和变量

def cheese_and_crackers(cheese_count, boxes_of_crackers):  
    print "You have %d cheeses!" % cheese_count  
    print "You have %d boxes of crackers!" % boxes_of_crackers  
    print "Man that's enough for a party!"  
    print "Get a blanket. \n"  
      
      
print "We can just give the function numbers directly:"  
cheese_and_crackers(20,30)  
  
  
  
  
print "OR, we can use variables from our script:"  
amount_of_cheese = 10  
amount_of_crackers = 50  
  
  
cheese_and_crackers(amount_of_cheese, amount_of_crackers)  
  
  
  
  
print "We can even do math inside too:"  
cheese_and_crackers(10 + 20, 5 + 6)  
  
  
  
  
print "And we can combine the two, variables and math:"  
cheese_and_crackers(amount_of_cheese + 100, amount_of_crackers + 1000)  

ex21 函数返回值

def add(a,b):
    print("ADDING %d + %d" %(a,b))
    return a + b

def subtract(a,b):
    print("SUBTRACTING %d - %d" % (a,b))
    return a - b

def multipyl(a,b):
    print("MULTIPLYTING %d * %d" % (a,b))
    return a * b

def divide(a,b):
    print("DIVIDING %d / %d" % (a,b))
    return a / b

print("Let's do some math with just functions!")

age = add(30,5)

height = subtract(78,4)

weight = multipyl(90,2)

iq = divide(100,2)

print("Age:%d,Height:%d,Wight:%d,IQ:%d" %(age,height,weight,iq))

#A puzzle for the extra credit,type it in anyway.
print("Here is a puzzle.")

what = add(age,subtract(height,multipyl(weight,divide(iq,2))))
print("That becomes:",what,"Can you do it by hand?")