Var
A,b,c,x,sum: integer;
Y: real;
Begin
WriteLn('vvedite x');ReadLn(x);
WriteLn('vvedite a');ReadLn(a);
WriteLn('vvedite b');ReadLn(b);
WriteLn('vvedite c');ReadLn(c);
Sum:= a+b+c;
If sum > 20 then begin
Y:= 2*x-1;
End else begin
3*sqr(x)*x-1;
End;
End.