Performance on a simple calc like this honestly wouldn't make any difference

dude calm down

this code smells determination

instead of "count the number of the element which smaller than n and return it."

it should be "count the numbers of elements which are smaller than n and return it."

the problem with the first one is that gives the intention that we are supposed to pick the index of the element that's smaller than n, instead of how many

What do you mean "but why"?

This helped...now the question is...

But why?

Hey!
'hex' if for hexadecimal numeral system.
While decimal numeral system goes from 0-9 (if you count from 0 to 9 you will find out that there are already 10 numbers. In decimal numeral system the last digit that is equal to '9', so the very next number will be '1'+0, '1'+1 and so on.) The hexadecimal numeral system goes from 0 to F (16 numbers)
here is the first +32 digits:
0
1
2
3
4
5
6
7
8
9
A (is equal to 10)
B
C
D
E
F (is equal to 15 in decimal )
10 (is equal to 16)
11
12
13
14
15
16
17
18
19
1A
1B
1C
1D
1E
1F
20
21
and so on
Hope it helped you out

Please, can you give more details about the exercise? Like what's a hex and a decimal number? What are examples of translating from hex to decimal?