int main()
{
float val;
int month,day,p;
scanf("%f %d %d %d",&val,&month,&day,&p);
if(month==11&&day==11&&p==0) val=val*0.7;
else if(month==11&&month==11&&p==1) val=val*0.7-50;
else if(month==12&&day==12&&p==0) val=val*0.8;
else if(month==12&&day==12&&p==1) val=val*0.8-50;
if(val>=0) printf("%.2f",val);
else printf("0.00");
return 0;
}