Python的if...else...、for...in...、

if...else...：

# -*- coding: utf-8 -*-
a = input("age:")
age = int(a)
if a:
    if age > 1000:
        print("神仙")
    elif age > 100:
        print("长寿")
    else:
        print("凡人")
else:
    print("年龄为空")

for...in...：

#计算0到9的和
sum = 0
for x in range(10):
    sum += x
print(sum)

while:

#计算0到9的和
sum = 0
n = 9
while n > 0:
    sum += n
    n -= 1
print(sum)

break和continue：

break跳出循环，continue跳出此次循环进入下一次循环，都要配合if用。

sum = 0
n = 9
while n > 0:
    n -= 1
    if n % 2 == 0:
        sum += n
        continue
print(sum) ----------------> 20

sum = 0
n = 9
while n > 0:
    n -= 1
    if n % 2 == 0:
        sum += n
        break
print(sum) ----------------> 8