s = set(['Adam', 'Lisa', 'Paul'])
L = ['Adam', 'Lisa', 'Bart', 'Paul']
for name in L:
if name in s:
s.remove(name)
else:
s.add(name)
print s
L = ['Adam', 'Lisa', 'Bart', 'Paul']
for name in L:
if name in s:
s.remove(name)
else:
s.add(name)
print s
2016-08-22
d = {'a':[1,2,3],12:'123',('a','b'):True}
print (d)
print (d['a'])
print (d[12])
print (d[('a','b')])
以上都是正确的!
print (d)
print (d['a'])
print (d[12])
print (d[('a','b')])
以上都是正确的!
2016-08-22
L = range(1, 101)
print L[0:10]
print L[2::3]
print L[4::5][0:10]
print L[0:10]
print L[2::3]
print L[4::5][0:10]
2016-08-22
def average(*args):
sum=0.0
n=0.0
for x in args:
sum=sum+x
n=n+1
if n!=0:
return sum/n
else:
return n
print average()
print average(1, 2)
print average(1, 2, 2, 3, 4)
sum=0.0
n=0.0
for x in args:
sum=sum+x
n=n+1
if n!=0:
return sum/n
else:
return n
print average()
print average(1, 2)
print average(1, 2, 2, 3, 4)
2016-08-22
L = ['Adam', 'Lisa', 'Bart']
L.insert(3,'Adam')
L[0] = L[2]
L[2] = L[3]
L.pop()
print L
L.insert(3,'Adam')
L[0] = L[2]
L[2] = L[3]
L.pop()
print L
2016-08-22
sum = 0
x = 1
n = 1
while True:
if n > 20:
break
sum = sum + x
x = x * 2
n = n + 1
print sum
x = 1
n = 1
while True:
if n > 20:
break
sum = sum + x
x = x * 2
n = n + 1
print sum
2016-08-22
import math
def quadratic_equation(a, b, c):
te=b*b-4*a*c
if te>=0:
x1=(-b+math.sqrt(te)) / (2 * a)
x2=(-b-math.sqrt(te)) / (2 * a)
return x1,x2
else:
return
def quadratic_equation(a, b, c):
te=b*b-4*a*c
if te>=0:
x1=(-b+math.sqrt(te)) / (2 * a)
x2=(-b-math.sqrt(te)) / (2 * a)
return x1,x2
else:
return
2016-08-22