How is it possible to use a while loop to print even numbers 2 through 100?

问题

I am a beginner and I am stuck on this problem, "Write a python code that uses a while loop to print even numbers from 2 through 100. Hint ConsecutiveEven differ by 2."

Here is what I came up with so far:

 while num in range(22,101,2):
              print(num)

回答1:

Use either for with range(), or use while and explicitly increment the number. For example:

>>> i = 2
>>> while i <=10: # Using while
...    print(i)
...    i += 2
...
2
4
6
8
10

>>> for i in range(2, 11, 2): # Using for
...    print(i)
...
2
4
6
8
10

回答2:

Your code has several problems:

• Substituting while for a statement with for syntax. while takes a bool, not an iterable.
• Using incorrect values for range: you will start at 22.

With minimal changes, this should work:

for num in range(2, 101, 2):
    print(num)

Note that I used 101 for the upper limit of range because it is exclusive. If I put 100 it would stop at 98.

If you need to use a while loop:

n = 2
while n <= 100:
    print (n)
    n += 2

回答3:

Here is how to use the while loop

 while [condition]:
     logic here

using while in range is incorrect.

num = 0
while num <=100:
    if num % 2 == 0:
        print(num)
    num += 1

回答4:

This is what I'd try:

i=2
while i <= 100:
    if ( i % 2==0):
        print (i, end=', ')
    i+=1

来源：https://stackoverflow.com/questions/40094424/how-is-it-possible-to-use-a-while-loop-to-print-even-numbers-2-through-100