main()
{
int c,S;
float P,w,d,f;
scanf("%f,%f,%d",&P,&w,&S);
if(S>=3000) c=12;
else c=S/250;
switch(c)
{
}
case0: d=0; break;
case1: d=2; break;
case2:
case3: d=5; break;
case4:
case5:
case6:
case7: d=8; break;
case8:
case9:
case10:
case11: d=10; break;
case12:
f=P*w*S*(1-d/100.0);
printf("freight=%15.4f",f);
}