求1-2+3-4+5 ... 99的所有数的和 

1  sum = 0
2  count = 1
3  while count < 100:
4      if count % 2 == 0:
5          sum = sum - count
6      else:
7          sum = sum + count
8      count += 1
9  print(sum)

 

posted @ 2018-10-16 00:11  梦潇幻影  阅读(268)  评论(0)    收藏  举报