import math
def quadratic_equation(a, b, c):
d = b*b - 4*a*c
if d >= 0:
x1 = (-b + math.sqrt(d))/(2*a)
x2 = (-b - math.sqrt(d))/(2*a)
return x1,x2
else:
x1 = (-b + i * math.sqrt(d))/(2*a)
x2 = (-b - i * math.sqrt(d))/(2*a)
return x1,x2
def quadratic_equation(a, b, c):
d = b*b - 4*a*c
if d >= 0:
x1 = (-b + math.sqrt(d))/(2*a)
x2 = (-b - math.sqrt(d))/(2*a)
return x1,x2
else:
x1 = (-b + i * math.sqrt(d))/(2*a)
x2 = (-b - i * math.sqrt(d))/(2*a)
return x1,x2
2016-04-23
最赞回答 / 清波
题主的问题令我疑惑。是说 先pop(2) 然后pop(3) 么, 就题中 的例子, pop(2) 之后 的列表只剩下三个元素了,最大的index 就是2, 如果在pop(3) 的话, 或报出 IndexError 的。
2016-04-23
def square_of_sum(L):
sum = 0
for i in L:
sum += i * i
return sum
print square_of_sum([1, 2, 3, 4, 5])
print square_of_sum([-5, 0, 5, 15, 25])
sum = 0
for i in L:
sum += i * i
return sum
print square_of_sum([1, 2, 3, 4, 5])
print square_of_sum([-5, 0, 5, 15, 25])
2016-04-23
d = {
'Adam': 95,
'Lisa': 85,
'Bart': 59
}
print 'Adam:' + str(d['Adam'])
print 'Lisa:' + str(d['Lisa'])
print 'Bart:' + str(d['Bart'])
'Adam': 95,
'Lisa': 85,
'Bart': 59
}
print 'Adam:' + str(d['Adam'])
print 'Lisa:' + str(d['Lisa'])
print 'Bart:' + str(d['Bart'])
2016-04-23
s = set(['Adam','Lisa', 'Paul'])
L = ['Adam', 'Lisa', 'Bart', 'Paul']
for x in L:
if x in s:
s.remove(x)
else:
s.add(x)
print s
L = ['Adam', 'Lisa', 'Bart', 'Paul']
for x in L:
if x in s:
s.remove(x)
else:
s.add(x)
print s
2016-04-23
for x in [1,2,3,4,5,6,7,8,9]:
for y in [1,2,3,4,5,6,7,8,9]:
if x < y:
print int(str(x)+str(y))
for y in [1,2,3,4,5,6,7,8,9]:
if x < y:
print int(str(x)+str(y))
2016-04-23
s = set([('Adam', 95), ('Lisa', 85), ('Bart', 59)])
for x in s:
print x[0],':',x[1]
for x in s:
print x[0],':',x[1]
2016-04-23
最新回答 / 清波
我要先吐槽下, 万恶的歪果仁, 发明语言的时候为什么不用Unicode 做默认字符编码, 呃 突然感觉这么说 特别的没良心。。。Python 2.x 中 u"xx" 是在定义 unicode 字符串。 r"..." 是在定义原始字符串,也就是“转义转义字符” 哈哈,我随口说的,题主可以自己搜索官方的正经解释。 而ur"xxx" 则是 综合两家之长, 课程中显示不正确 只是慕课网的正确性验证做的不好, 并不是你写的不对, 如果想通过验证, 字符串前面不要加 修饰就好了。
2016-04-23
d = {
'Adam': 95,
'Lisa': 85,
'Bart': 59
}
for key in d:
print key,':',d[key]
'Adam': 95,
'Lisa': 85,
'Bart': 59
}
for key in d:
print key,':',d[key]
2016-04-23
for x in range(1, 10):
for y in range(0, 10):
if x < y:
print x * 10 + y
for y in range(0, 10):
if x < y:
print x * 10 + y
2016-04-23
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:
print x * 10 + y
for y in [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]:
if x < y:
print x * 10 + y
2016-04-23
sum = 0
x = 0
while True:
x = x + 1
if x > 100:
break
elif x % 2 == 0:
continue
else:
sum += x
print sum
x = 0
while True:
x = x + 1
if x > 100:
break
elif x % 2 == 0:
continue
else:
sum += x
print sum
2016-04-23