while loop
When entering the loop condition is satisfied, enter the circulation, when the condition is not satisfied, out of the loop
Example 1:
i =0
while i < 3:
i+=1
print(i)
After the results:
Python language allows a circulation loop embedded inside another
Example 2:
i,j =1,10
while i < 20:
while i <j:
j-=5
i+=5
print (i,j)
After the results:
The following cases combined with a better understanding
Case 1:
5 apple, pear 4, 3 watermelon, cantaloupe 6, three peach, orange 7
While loop to find the peaches from the above, it counts the number of peaches, and judgment is odd or even
fruits = '5 apples, pears 4, 3 watermelon, cantaloupe 6, three peach, orange 7'
I = 0
fruits_len = len (Fruits)
the while I <fruits_len:
IF Fruits [I: I + 2 ] == 'peach':
Print ( "peach in that position:" + fruits [i-6 : i-3] + " and" + fruits [i + 5: i + 7] + " between")
IF int (Fruits [I + 2])% 2 == 0:
Print ( "total number of peaches% d, the even-numbered"% int (Fruits [I + 2]))
the else:
Print ( "total number of peaches% d, odd "% int (Fruits [I + 2]))
I + =. 1
After the results:
Case 2: The user interface Log
1. Enter the user name and password
2. determine the user name and password are correct
3. After three failed login error
. 3 = I
the while 0 <I <=. 3:
User = INPUT ( 'Please enter your account number:')
password = INPUT ( 'Enter your password:')
IF User == 'ADMIN' and password == '123456 ':
Print ( "Login successful")
BREAK
the else:
Print ( "Login failed chance you have% d"% int (i-1))
i - = 1
the else:
Print ( "more than three times the number of login, please wait try again ")
Operating results Results:
login successful
Login failed
