var i,a,sum:longint;
begin
sum:=0;
for i:=1 to 6 do begin readln(a); if(a>0) then sum:=sum+a; end;
writeln(sum);
end.
var i,a,sum:longint;
begin
sum:=0;
for i:=1 to 6 do begin readln(a); if(a>0) then sum:=sum+a; end;
writeln(sum);
end.