program P;
var a,b:integer;
function f(var a:integer; b:integer):integer;
begin
if a>0 then f:=f(a,b-1)+2
else if b<0 then f:=f(a,b+1) -1
else f:=b;
end;
begin
a:=1; b:=2;
writeln(f(a,b))
end.
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