Purpose of a “.f” appended to a number?

Question

I saw \"1/3.f\" in a program, and wondered what the \".f\" was for. So tried my own program:

#include
using namespace std;
int main()
{
              


        

Answer 1

By default 3.2 is treated as double; so to force the compiler to treat it as float, you need to write f at the end.

Just see this interesting demonstration:

float a = 3.2;
if ( a == 3.2 )
    cout << "a is equal to 3.2"<

Output:

a is not equal to 3.2
b is equal to 3.2f

Do experiment here at ideone: http://www.ideone.com/WS1az

Try changing the type of the variable a from float to double, see the result again!