Python--控制流

控制流

if语句

• if 判断条件：

game = 1000
money = 100000
if game<2000:
    game+=1000
    money-=1000
print('You have '+str(game)+'RMB in your game,'
      + 'you have '+str(money)+'RMB in your money!')

You have 2000RMB in your game,you have 99000RMB in your money!

• if 、else 、elif

  people='Tom'
  if people=='Mary':
    print('Hello Mary!')
  elif people=='Tom':
    print('Hello,Tom~')
  else:
    print('Go away~')

  Hello,Tom~

  ---

  for循环

  names = ['Tom', 'mary', 'jimmy', 'William']
  New_names = []
  for name in names:
    New_names.append(name.title())
  print(New_names)

  ['Tom', 'Mary', 'Jimmy', 'William']

  ---

• range(star，stop，step)和for结合进行循环

  • star 开始数值，不填为0
  • stop 结束数值，需要填
  • step 间隔数值，不填为1

for i in range(1, 5, 2):
    print(i)

1
3

while循环

• while

  deck = [1, 2, 3, 4, 5, 6, 7, 8, 9]
  equipped = []
  while sum(equipped) <= 20:
    print(equipped)
    equipped.append(deck.pop())
  print(equipped)

  [9]
  [9, 8]
  [9, 8, 7]

  ---

• while与break

  while True:
    word=input('Enter string to capitalize[type q to quit]:')
    if word == 'q':
        break
    print(word.capitalize())

  Enter string to capitalize[type q to quit]:hello
  Hello
  Enter string to capitalize[type q to quit]:q
   

  ---

• while与continue

  while True:
    value = input('Even number please~[enter q to quit]:')
    if value == 'q':
        break
    number = int(value)
    if number % 2 == 0:
        continue
    print('I said even number,are you blind?')

  Even number please~[enter q to quit]:2
  Even number please~[enter q to quit]:6
  Even number please~[enter q to quit]:8
  Even number please~[enter q to quit]:5
  I said even number,are you blind?
  Even number please~[enter q to quit]:q