L = [95.5, 85, 59]
print L[-1]
print L[-2]
print L[-3]
print L[-4]
print L[-1]
print L[-2]
print L[-3]
print L[-4]
2017-02-24
L = [95.5,85,59]
print L[0]
print L[1]
print L[2]
print L[-1]
print L[0]
print L[1]
print L[2]
print L[-1]
2017-02-24
and中，如果第一个变量为真，结果直接是第二个变量，与真假无关；如果第一个变量为假，结果直接是第一个变量，与第二个变量真假的无关。
or中，如果第一个变量为真，结果直接为第一个，与第二个真假无关；如果第一个变量为假，结果直接是第二个变量，与其真假无关
or中，如果第一个变量为真，结果直接为第一个，与第二个真假无关；如果第一个变量为假，结果直接是第二个变量，与其真假无关
2017-02-24
d = { 'Adam': 95, 'Lisa': 85, 'Bart': 59, 'Paul': 74 }
sum = 0.0
for k, v in d.items():
sum = sum + v
print k,':',v
print 'average', ':', sum/len(d)
sum = 0.0
for k, v in d.items():
sum = sum + v
print k,':',v
print 'average', ':', sum/len(d)
2017-02-23
import math
def quadratic_equation(a, b, c):
nx=-b/(2*a)+(math.sqrt(b*b-4*a*c))/(2*a)
ny=-b/(2*a)-(math.sqrt(b*b-4*a*c))/(2*a)
return nx,ny
print quadratic_equation(2, 3, 0)
print quadratic_equation(1, -6, 5)
def quadratic_equation(a, b, c):
nx=-b/(2*a)+(math.sqrt(b*b-4*a*c))/(2*a)
ny=-b/(2*a)-(math.sqrt(b*b-4*a*c))/(2*a)
return nx,ny
print quadratic_equation(2, 3, 0)
print quadratic_equation(1, -6, 5)
2017-02-23
def average(*args):
if len(args)>0:
return sum*1.0/len(args)
else:
return 0.0
print average()
print average(1, 2)
print average(1, 2, 2, 3, 4)
if len(args)>0:
return sum*1.0/len(args)
else:
return 0.0
print average()
print average(1, 2)
print average(1, 2, 2, 3, 4)
2017-02-23
# _*_ coding: utf-8 _*_
sum=0
n=0
while True:
n=n+1
if n%2==0:
continue
if n>100:
break
sum=sum+n
print(sum)
sum=0
n=0
while True:
n=n+1
if n%2==0:
continue
if n>100:
break
sum=sum+n
print(sum)
2017-02-23
def average(*args):
if len(args)==0:
return 0.0
return (sum(args))/(len(args)+0.0)
print average()
print average(1, 2)
print average(1, 2, 2, 3, 4)
if len(args)==0:
return 0.0
return (sum(args))/(len(args)+0.0)
print average()
print average(1, 2)
print average(1, 2, 2, 3, 4)
2017-02-23
sum=0
n=0
while True:
sum=sum+2**n
n=n+1
if n>19:
break
print(sum)
n=0
while True:
sum=sum+2**n
n=n+1
if n>19:
break
print(sum)
2017-02-23
for x in [ '1','2','3','4','5','6','7','8','9' ]:
for y in [ '0','1','2','3','4','5','6','7','8','9' ]:
if x >= y :
continue
print x,y
for y in [ '0','1','2','3','4','5','6','7','8','9' ]:
if x >= y :
continue
print x,y
2017-02-23