program ctlhn;
uses crt;
var n, a1, a2, a3, tien: word;
begin
clrscr;
write('nhap n:'); readln(n);
write('nhap a1:'); readln(a1);
write('nhap a2:'); readln(a2);
write('nhap a3:'); readln(a3);
tien := a1;
write('cuoc phi:');
if n=0 then write(0) else begin
if n<=10 then tien:=tien+a2;
if n>=11 then tien:=tien+a2+a3;
write(tien);
end;
readln;
end.