#include<stdio.h>
#include<math.h>
main()
{
   float x,f;
   for(x=-3.0;x<=3.0;x+=0.3){
      f=x-3.0*exp(-x);
      if(f>0.0){
         printf("x=%8.2f f=%15.5f sign = +\n",x,f);
      }else if(f==0.0){
         printf("x=%8.2f f=%15.5f sign = 0\n",x,f);
      }else{
         printf("x=%8.2f f=%15.5f sign = -\n",x,f);
      }
   }
   return(0);
}