# include<stdio.h>
# include<math.h>
main (void)
float x,y;
{scanf("%f%f",&x,&y);
if (x<=1)
 y=exp()+1;
 else if (x>1&&5<=x)
 y=-4*x+5;
 else if (x>5&&10<=x)
 y=2*x-1;

  else
  y=3*x-11;
  printf("%f\n",y);
  }