d = {
'Adam': 95,
'Lisa': 85,
'Bart': 59
}
print 'Adam:',d.get('Adam')
if 'Lisa' in d:
print 'Lisa:',d['Lisa']
print 'Bart:',d['Bart']
'Adam': 95,
'Lisa': 85,
'Bart': 59
}
print 'Adam:',d.get('Adam')
if 'Lisa' in d:
print 'Lisa:',d['Lisa']
print 'Bart:',d['Bart']
2017-02-13
for x in [0,1,2,3,4,5,6,7,8,9]:
for y in [0,1,2,3,4,5,6,7,8,9]:
if x<y:
if x==0:
continue
print x,y
……纯新手能做成这样很不错了
for y in [0,1,2,3,4,5,6,7,8,9]:
if x<y:
if x==0:
continue
print x,y
……纯新手能做成这样很不错了
2017-02-13
自己敲的代码,答案101,2450,2499,2550,5050都有,就是没有2500,
看了答案才会……之前一直把continue用法搞错了,现在想来,大概就是把不要的条件,就放在continue前面的if里去
另外,sum=sum+x的位置也很重要,要先满足continue语句才能执行这一句
看了答案才会……之前一直把continue用法搞错了,现在想来,大概就是把不要的条件,就放在continue前面的if里去
另外,sum=sum+x的位置也很重要,要先满足continue语句才能执行这一句
2017-02-13
sum=0
x=1
while True:
sum+=x
x=x*2
if x>2**19:
break
print sum
x=1
while True:
sum+=x
x=x*2
if x>2**19:
break
print sum
2017-02-13
思路:4个数相加,然后除以4
转化成代码
思路:定义一个s,for s in L:
然后就不知道怎么把“4个数相加”转化成代码了,这就是逻辑思维的重要性?
转化成代码
思路:定义一个s,for s in L:
然后就不知道怎么把“4个数相加”转化成代码了,这就是逻辑思维的重要性?
2017-02-13
def greet(x='world'):
print ('hello,'+x+'.')
greet()
greet('Bart')
print ('hello,'+x+'.')
greet()
greet('Bart')
2017-02-13
L=(1,2,3,4,5,6,7,8,9)
for x in L:
for y in L:
if x<y:
print '%d'%x+'%d'%y
for x in L:
for y in L:
if x<y:
print '%d'%x+'%d'%y
2017-02-12
def move(n,a,b,c):
if n == 1:
print ('move ',n,a ,'-->',c)
else:
move(n-1,a,c,b)
print('move ',n,a ,'-->',c)
move(n-1,b,a,c)
move(4, 'a', 'b', 'c')
if n == 1:
print ('move ',n,a ,'-->',c)
else:
move(n-1,a,c,b)
print('move ',n,a ,'-->',c)
move(n-1,b,a,c)
move(4, 'a', 'b', 'c')
2017-02-12
import math
def quadratic(a,b,c):
if a == 0:
if b == 0:
return 'x'
else:
x = -c/b
return x
else:
midx = (b*b-4*a*c)
x1 = (-b+math.sqrt(midx)/(2*a)
x2 = (-b-math.sqrt(midx)/(2*a)
return x1,x2
def quadratic(a,b,c):
if a == 0:
if b == 0:
return 'x'
else:
x = -c/b
return x
else:
midx = (b*b-4*a*c)
x1 = (-b+math.sqrt(midx)/(2*a)
x2 = (-b-math.sqrt(midx)/(2*a)
return x1,x2
2017-02-12
def square_of_sum(L):
return sum(x*x for x in L)
print square_of_sum([1,2,3,4,5])
print square_of_sum([-5,0,5,15,25])
return sum(x*x for x in L)
print square_of_sum([1,2,3,4,5])
print square_of_sum([-5,0,5,15,25])
2017-02-12
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
2017-02-12