Can anyone tell me why this code gives me True but 4 is not in the list??please tell me the concept

Question

num=[10,9,8,6,7,5]
num[0]=num[1]-5
print(4 in num)

Answer 1

because the first value in the list is reassigned to the value 4 before you check if 4 is in the list.

num[1] is the second value in the list: 9.
9 - 5 is 4

Answer 2

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Answer 3

Hi! Becouse the third line of code takes the second element of the array-this is 9, subtracts 5 and inserts the result (9-5=4) into the zero element of the array. i.e., in fact, replaces 10 with 4

Answer 4

Thanks Slick and Ярослав Вернигора(Yaroslav Vernigora) ...now i can understand😅

Answer 5

Or just use any modern IDE, they usually have this feature to single step through code and also to keep watch on certain variables you want.

Answer 6

Somil Khandelwal becouse The ▪︎in ▪︎ operator returns True if the specified substring is part of another string. Otherwise, it returns False .

Answer 7

it all depends on where you write that and i dont see your code, soo...

Answer 8

The in operator returns True if the specified substring is part of another string. Otherwise, it returns False .

Answer 9

IDE's for Python:

PyCharm
Spyder
Thonny
Eclipse + PyDev
Sublime Text
Atom
Visual Studio Code

Answer 10

num[1] which is 9 in your list
num[1]-5 means 9-5
that's why you got 4

Answer 11

num[0]=num[1] so its true

Answer 12

the second line num[0]=num[1]-5 replaces the 10 with a 4(9-5). When the 3rd line runs, 4 is in the list this True

Answer 13

But when i write
print(num)
It gives me[10,9,8,6,7,5]
Why it doesn't give me 4?

Answer 14

Bcos, num[0] has been replaced by num[1]-5. i.e. 10 has been replaced by 9-5=4. So, d 1st no in the list is now 4 not 10 again.