d = { 'Adam': 95, 'Lisa': 85, 'Bart': 59, 'Paul': 74 }
sum = 0.0
for i in d.values():
sum = sum+i
length=len(d.values())
print sum/length
sum = 0.0
for i in d.values():
sum = sum+i
length=len(d.values())
print sum/length
2016-08-16
sum = 0
x = 1
n = 1
while True:
sum=sum+x
x=x*2
n=n+1
if n>20:
break
print sum
那个慕粉cyh,你的if n>20后面的:丢了
x = 1
n = 1
while True:
sum=sum+x
x=x*2
n=n+1
if n>20:
break
print sum
那个慕粉cyh,你的if n>20后面的:丢了
2016-08-16
L = ['Adam', 'Lisa', 'Bart']
a = L[0]
L[0] = L[2]
L[2] = a
print L
a = L[0]
L[0] = L[2]
L[2] = a
print L
2016-08-16
a = 'python'
print 'hello,', a or 'world'
b = ''
print 'hello,', b or 'world'
因为或运算中只要有一个布尔值为 True,计算结果就是 True;而a为true所以计算结果返回world,所以为Hello world.
因为Python把0、空字符串''和None看成 False,其他数值和非空字符串都看成 True。而b为False,所以python将world看作world即Hello python.
print 'hello,', a or 'world'
b = ''
print 'hello,', b or 'world'
因为或运算中只要有一个布尔值为 True,计算结果就是 True;而a为true所以计算结果返回world,所以为Hello world.
因为Python把0、空字符串''和None看成 False,其他数值和非空字符串都看成 True。而b为False,所以python将world看作world即Hello python.
2016-08-16
自己下的python GUI工具,输入了上述结果,发现print L[-4]的结果是
Traceback (most recent call last):
File "<pyshell#4>", line 1, in <module>
print L[-4]
IndexError: list index out of range
Traceback (most recent call last):
File "<pyshell#4>", line 1, in <module>
print L[-4]
IndexError: list index out of range
2016-08-16
s = set(['Adam', 'Lisa', 'Paul'])
L = ['Adam', 'Lisa', 'Bart', 'Paul']
t =set(L)
s=t-s
print s
L = ['Adam', 'Lisa', 'Bart', 'Paul']
t =set(L)
s=t-s
print s
2016-08-16
有没有跟我一样,一直写分割都忘了字符串可以单个写成s[0]了。。想想也是醉了
def firstCharUpper(s):
return s[:1].upper()+s[1:]
print firstCharUpper('hello')
print firstCharUpper('sunday')
print firstCharUpper('september')
def firstCharUpper(s):
return s[:1].upper()+s[1:]
print firstCharUpper('hello')
print firstCharUpper('sunday')
print firstCharUpper('september')
2016-08-16
答案竟然用len。。。
然而我用的c的思想,强制加进去一个计数器。。。
def average(*args):
sum=0.0
j=0
for i in args:
sum=sum+i
j=j+1
if j!=0:
sum=sum/j;
print sum
print average()
print average(1, 2)
print average(1, 2, 2, 3, 4)
然而我用的c的思想,强制加进去一个计数器。。。
def average(*args):
sum=0.0
j=0
for i in args:
sum=sum+i
j=j+1
if j!=0:
sum=sum/j;
print sum
print average()
print average(1, 2)
print average(1, 2, 2, 3, 4)
2016-08-16