python学习笔记

python是完全面向对象语言

字符串

r

R

r"Newlines are indicated by \n"

# FILENAME : 2.py
i = 5
print i
i=i+1;print i;

s='''this is a multi-line string.
this is the second line.'''
print s

q='''this is a multi-line string.\
this is the second line.'''
print q

jiao.geng@jiaogeng-Latitude-E5450:~/python$ python 2.py
5
6
this is a multi-line string.
this is the second line.
this is a multi-line string.this is the second line.

#!/usr/bin/python
# Filename: if.py

number = 23
guess = int(raw_input('Enter an integer : '))

if guess == number:
print 'Congratulations, you guessed it.' # New block starts here
print "(but you do not win any prizes!)" # New block ends here
elif guess < number:
print 'No, it is a little higher than that' # Another block
# You can do whatever you want in a block ...
else:
print 'No, it is a little lower than that'
# you must have guess > number to reach here

print 'Done'
# This last statement is always executed, after the if statement is executed

$ python if.py

Enter an integer : 50

No, it is a little lower than that

Done

$ python if.py

Enter an integer : 22

No, it is a little higher than that

Done

$ python if.py

Enter an integer : 23

Congratulations, you guessed it.

(but you do not win any prizes!)

Done