print 1 + 1 == 2print 1 + 1 != 2print 1 + 1 == 2 and 1 + 1 == 3print 1 + 1 == 2 or 1 + 1 == 3print not 1 + 1 == 2print 1 in [1, 2, 3]
输出:
True
False
False
True
False
True
2.if
light = "red"
if light == "red":
print "Stop!"
elif light == "green":
print "Go!"
elif light == "yellow":
print "Slow down!"
3.while
a = 100
while a<100:
a = a +1
print a
4. for in
contact = {"Li Lei" : "1303030", "HanMeimei" : "1450303"}
for i in contact:
print i, contact[i]
输出：
"Li Lei" : "1303030"
"HanMeimei" : "1450303"
5.break continue
意思与其他大部分语言相同
6.自定义函数
def addNum(num):
a = 0
for i in num:
a = a + i
return a
num = [ 1 ,3 ,4 ,5 , 9]
print addNum(num)
7.函数作用域
与C++很像
x = 0
y = 0
def changex():
global x //global 可以在函数里面使用函数外面的变量
x = 10
y = 10
print x
print y
changex()
print x
print y
8.import
import math //导入包
print math.pi
print dir(math) //dir可以查看包的所有方法
