var
    a, a1, a2: integer;

begin
    read(a);
    a1 := a div 1000 mod 10 + a div 100 mod 10;
    a2 := a div 10 mod 10 + a mod 10;
    writeln(a1 = a2);
end.

Verified answer

var 

a,a1,a2,a3,a4:integer;

begin

readln (a);

a1:=a div 1000 ;

a2:=a div 100 mod 10;

a3:=a div 10 mod 10;

a4:=a mod 10;

if (a1+a2) = (a3+a4) then writeln ('Равена')

else

writeln ('Не равна');

end.