Next: , Up: Type Conversions   [Contents][Index]

24.1 Explicit Type Conversion

You can do explicit conversions using the unary cast operator, which is written as a type designator (see Type Designators) in parentheses. For example, (int) is the operator to cast to type int. Here’s an example of using it:

  double d = 5.5;

  printf ("Floating point value: %f\n", d);
  printf ("Rounded to integer: %d\n", (int) d);

Using (int) d passes an int value as argument to printf, so you can print it with ‘%d’. Using just d without the cast would pass the value as double. That won’t work at all with ‘%d’; the results would be gibberish.

To divide one integer by another without rounding, cast either of the integers to double first:

(double) dividend / divisor
dividend / (double) divisor

It is enough to cast one of them, because that forces the common type to double so the other will be converted automatically.

The valid cast conversions are: