C Standard Library

C <math.h> - ceil() Function



The C <math.h> ceil() function returns the next highest integer value by rounding up the specified number, if necessary. In other words, it rounds the fraction UP of the given number.

Syntax

double ceil (double x);
float ceilf (float x);
long double ceill (long double x);

Parameters

x Specify a number.

Return Value

Returns the next highest integer value by rounding UP the specified number, if necessary.

Example:

In the example below, ceil() function is used to round the fraction UP of the specified number.

#include <stdio.h>
#include <math.h>
 
int main (){
  printf("%lf\n", ceil(10.5));
  printf("%lf\n", ceil(-10.5));
  printf("%lf\n", ceil(0.5));
  printf("%lf\n", ceil(-0.5));   
  return 0;
}

The output of the above code will be:

11.000000
-10.000000
1.000000
-0.000000

❮ C <math.h> Library