Floating Point Versus Integer Divide

Look at the program:

int main() {

float ans;

ans=5/10;

printf("%f",ans);

return 0;

}

what is the output?

The output is not like this: 0.50000

The output is 0.000000

because int/int = int

so change the program to

int main(void) {

float ans;

ans=5/10.0;

printf("%f",ans);

return 0;

}

the above program is (int/float)

so the output is now 0.500000

NOTE:

int/int = int

int/float = float

float/int = float

float/float = float

The above table can be summarized as: integer division takes place only when both elements are integers.

The below mentioned information is from: Practical C Programming, Third Edition - O'Reilly Media

The division operator is special. There is a vast difference between an integer divide

and a floating-point divide. In an integer divide, the result is truncated (any

fractional part is discarded). So the value of 19/10 is 1.

If either the divisor or the dividend is a floating-point number, a floating-point divide

is executed. So 19.0/10.0 is 1.9. (19/10.0 and 19.0/10 are also floating-point

divides; however, 19.0/10.0 is preferred for clarity.)