Long and short ?

Question

what are they? are they integeds? when would they be used?

Answer 1

suppose you are writing a program of simple Armstrong number that you can see to my profile.

in this case you know that a user can input as long as the value greater than 2^15. here comes the role of long int.

similarly as per your perception of the input taken by the user you have to use long wisely!

Answer 2

so use is based on experience . based on the range you indicated, right? 2 to 15 bytes? or am I misinterpretating?

I appreciate your help. the more I engage with these concepts and put them into practice, the more it will click. thank you very much .

Answer 3

there is something in C++ which is called "type specifier".
-type specifier are of 2 types.
1. sign specifier
2. size specifier

long and short fall under the category of size specifier.

size specifier changes the byte size of a variable.
e.i:-
int a; //by default it is "short int" 2 BYTES.
//range 2^15
but if we need to store an integer num of greater value than its range. then we can increase int byte size using Long specifier... as

long int b; //it takes 4 BYTES, range 2^31.

see its simple... similarly to increase float byte size we use...

long float c; // takes 8 bytes
long double; //takes 16 bytes

Answer 4

thank you, CodeRunner.

how do we know when we would put these to use?

Answer 5

I mean 2 to 15 as a range of value stored in a variable. not bytes.

Answer 6

Nice answer @CodeRunner, except for a small error:

Ranges for:
short int is 2^16, not 2^15
long int is 2^32, not 2^31

It is easier to see on a small number - lets say 3 bits. The range for a 3 bit number is 2^3 (i.e. 8), not 2^2 (i.e. 4) since the range is 0 to 7.

From the quality of your answer I actually suspect you knew this, but probably (I'm guessing here!) just got confused with the max (unsigned value) which will fit into a number - which is 2^16-1 for 16 bits (but note it is not 2^(16-1) which is what you specified). Either way, I think you probably know this!