python练习题

1 #1到100的和
2 a=0
3 sum=0
4 while a<=100:
5     sum+=a
6     a+=1
7 print(sum)

1 #1到500的奇数和
2 a=1
3 sum1=0
4 while a<500:
5     sum1+=a
6     a+=2
7 print(sum1)

1 #求1！+2！+。。。20！的和
2 a=1
3 sum2=0
4 for i in xrange(1,21):
5     a*=i
6     sum2+=a
7 print sum2

1 #排序
2 a=[2,32,43,453,54,6,576,5,7,6,8,78,7,89]
3 print(a)
4 a.sort()
5 print(a)
6 #正序
7 a.reverse()
8 print(a)
9 #反序