sum = 0
start = 1
while True:
if start%2 ==0:
sum = sum - start
else:
sum = sum + start
start = start + 1
if start == 101:
break
print(sum)
sum = 0
start = 1
while True:
if start%2 ==0:
sum = sum - start
else:
sum = sum + start
start = start + 1
if start == 101:
break
print(sum)
原文：https://www.cnblogs.com/wssaried/p/9785590.html