python基礎4--控制流
摘要：
1、if語句
結構：
if condition:
do something
elif other_condition:
do something
number = 60
guess = int(input('Enter an integer : '))
...
1、if語句
結構：
if condition:
do something
elif other_condition:
do something
number = 60
guess = int(input('Enter an integer : '))
if (guess == number):
# New block starts here
print('Bingo! you guessed it right.')
# New block ends here
elif (guess < number):
# Another block
print('No, the number is higher than that')
# You can do whatever you want in a block ...
else:
print('No, the number is alower than that')
# you must have guessed > number to reach here
print('Done')
2、迴圈語句允許我們執行一個語句或語句組多次，下面是在大多數程式語言中的迴圈語句的一般形式：
3、for語句
for i in range(1, 10):
print(i)
else:
print('The for loop is over')
#遍歷List
a_list = [1, 3, 5, 7, 9]
for i in a_list:
print(i)
#遍歷Tuple
a_tuple = (1, 3, 5, 7, 9)
for i in a_tuple:
print(i)
#遍歷Dict
a_dict = {'Tom':'111', 'Jerry':'222', 'Cathy':'333'}
for key in a_dict:
print(key, a_dict[key])
for (key, elem) in a_dict.items():
print(key, elem)
執行結果：
4、while語句
number = 59
guess_flag = False
while (guess_flag == False):
guess = int(input('Enter an integer : '))
if guess == number:
guess_flag = True
elif guess < number:
print('No, the number is higher than that, keep guessing')
else:
print('No, the number is alower than that, keep guessing')
print('Bingo! you guessed it right.')
5、break, continue, pass
(1) break 語句：跳出迴圈
(2) continue 語句：進行下一次 迴圈
(3) pass 語句：什麼都不做
number = 59
while True:
guess = int(input('Enter an integer : '))
if guess == number:
break
if guess < number:
print('No, the number is higher than that, keep guessing')
continue
else:
print('No, the number is alower than that, keep guessing')
continue
print('Bingo! you guessed it right.')
print('Done')