program intento3;
var s1:boolean;
    s2:boolean;

process p1;
begin
    repeat
    while s2=true do;
        s1:=true;

        writeln('ingresando a la seccion critica p1');

        s1:=false;
    forever
end;

process p2;
begin
    repeat
    while s1=true do;
        s2:=true;

        writeln('ingresando a la seccion critica p2');

        s2:=false;
    forever
end;

begin
    s1:=false;
    s2:=false;

    cobegin
    p1;
    p2;
    coend
end.