Why write f behind number?

Question

Hello
I dont und erstand the diffrence between:
float w= 3.56f
and
const float w = 3.56

Answer 1

@Rambo Nope
Focus only on KrOW's second advice

That is 3.58 is double precision while 3.5f is float precision

if you paste 3.58 like this
float f=3.58;
3.58 must be converted to float while itself double

but if you paste 3.58f like this
float f=3.58f;
3.58f won't be converted later

if compiler optimize about this. 3.58f and 3.58 won't have any difference at all
however you should leave f to tell your number is float

Answer 2

First: const indicate "the variable cannot change value":
float f= 3.5f;
const float cf = 4.5f;
cf = 10.3f; // error: dont compile. you cant reassign a const var

Second: 3.58 is a bit different from 3.58f. in the first case the value is a double (not float) value while in second case it is a float:
float d = 3.58; // here will be a double to float conversion
float f = 3.58f; // here will be no conversion

Answer 3

float w = 3.56 \\ normal float not a Constant
float w = 3.56f \\constant float
const float w = 3.56 \\ also Constant float, just a different way to write

Correct like this???

Same with long long (ll behindert number)?