+ 1
Why for loops is so strange when I use they with "if" and "or"?
I don't matter why when I make code like: For i in range(9): if i == 1 or 2: print ("P") "P" was printing 8 times, but not only 2. Why? I has been 1 once, and 2 similar once. P have to print only 2 times https://code.sololearn.com/cLcZBylXuT40/?ref=app
4 ответов
+ 4
Operator precedence,
https://www.google.com/url?sa=t&source=web&rct=j&url=https://docs.JUMP_LINK__&&__python__&&__JUMP_LINK.org/3/reference/expressions.html&ved=2ahUKEwid3s3muJzxAhWmwTgGHQ17AkoQFjALegQIHBAC&usg=AOvVaw20xmig3bG9EQm1_XcCKiMh&cshid=1623856603576
Look at the end part in above article .
"==" has higer precedence than "or", so python interpret it as ,
if (i=="!") or ","
in the above statement "," has some value , i.e. it isn't zero so if statement is always true , no mater if i is equal to "!" or not.
+ 1
I==1 or 2 is always true condition because it's equal to and evaluated as (i==1) or (2) : so anything is treated as true in boolean equivalent, other than value 0 or ""(empty string ) or null values
So it it like (I==1) or true => true so that's why "P" will be printed....
you need actually there I==1 or I==2
in python, it can shorten many types..
like (I in (1,2))
0
Try it in that way:
for i in range(2):
#if i == 1 or 2: not necessary
print ("P")
- 1
It’s printed 21 times in the linked example because len of text is 21. And its printed 9 times in the example above because range(9) means 9 times.