练习4

sum =0
i = 1
while i<=100:
sum += i
i +=1
print('1到100的和为%d'%sum)

运行结果
1到100的和为5050

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sum = 0
num = 1
while num <= 100:
sum += num
num += 2
print('1-100偶数的和：',sum)

运行结果

1-100偶数的和： 2500