floor

#include<stdio.h>
#include<math.h>
 
main()
{
   double number, result;
 
   printf("Enter a number to round it down ");
   scanf("%lf",&number);
 
   result = floor(number);
 
   printf("Original number =  %lf\n", number);
   printf("Number rounded down = %lf", result);
 
   return 0;
}