Art3mis - 4 months ago 26

C++ Question

This is my first question, so forgive me if I get something wrong.

I am very new to programming, and I came across a problem I can't find a solution to online. When using

`scanf`

For example,

`0020`

`16`

`0030`

`24`

`0100`

`64`

It seems to work with powers of

`8`

`8`

`0009`

`0`

`9`

There might be a simple rule I'm not aware of, I'm sorry if the answer is obvious. Thanks in advance for anyone who answers!

Answer

There are different notations for the popular bases (base 8, 10 and 16).

Base 8: Also known as Octal. You define a number as base 8 when you put a 0 in front of the input number. So when you input `020`

, it is read as `16`

in decimal.

Base 10: Also known as Decimal. You just write a number you want to input without any leading `0`

s. So when you input `20`

, it is read as `20`

.

Base 16: Also known as Hexadecimal. You write it with an `0x`

in the front. So inputting `0x20`

, it will be stored as `32`

in decimal.

If you are reading the number using `scanf()`

with format specifier as `%d`

`%i`

, then it is reading an octal number and interpreting it as an integer.