Returns the smallest integer that is greater than or equal to its
    argument.

    Format

      #include  <math.h>

      double ceil  (double x);

      float ceilf  (float x); (Integrity servers, Alpha)

      long double ceill  (long double x); (Integrity servers, Alpha)

1 - Argument

 x

    A real value.

2 - Return Value

    n                  The smallest integer greater than or equal to
                       the function argument.