#求1-100的所有数的和
n = 1
s = 0
while n < 101:
s = s + n
n = n + 1
print(s)
"""
#求1-2+3-4+5...99的所有数的和
n = 1
s = 0 # s是之前所有数的总和
while n < 100:
temp = n % 2
if temp == 0:
s = s -n
else:
s = s + n
n = n + 1
print(s)
"""