with Text_IO; use Text_io;
--generic
--	type ELEMENT is (<>);
--	SIZE:integer:=500;
--	with procedure Put(X:ELEMENT) is <>;
package body SET_OF is  -- array ELEMENT of BOOLEAN
    MAXEL:constant ELEMENT:=ELEMENT'VAL(SIZE);
    subtype INDEX is ELEMENT range ELEMENT'first..MAXEL;
    type DATA is array(INDEX) of boolean; -- Osets is access DATA
    ALL_FALSE:constant DATA:=DATA'(INDEX=>false);
 
 
  function  Member(I:ELEMENT; ISIN:ESET) return boolean is
  begin return ISIN.all(I);
  exception when CONSTRAINT_ERROR => return FALSE; -- ISIN=NULL
			--or I is outside range.
  end Member;
 
 
  function  Empty(ISIN:ESET) return boolean is --Empty(NULL_SET);
  begin --return ISIN.all/=all_false;
	for i in ISIN.all'range loop
		if ISIN.all(I) then return false;
		end if;
	end loop;
	return true;
  exception when CONSTRAINT_ERROR => return TRUE; -- ISIN=NULL
  end Empty;
 
  function  Full(ISIN:ESET) return boolean is
  begin return FALSE;
  end Full;
 
  procedure Empty(S:out ESET) is -- after S=NULL_SET
  begin S:=NULL;
  end;
 
  function  Max(S:ESET) return ELEMENT is
  begin for i in reverse S.all'range loop
		if S.all(I) then return I;
		end if;
	end loop;
	raise EMPTY_GET;
  exception when CONSTRAINT_ERROR => raise EMPTY_GET;
  end Max;
 
  function  Min (S:ESET) return ELEMENT is
  begin for i in S.all'range loop
		if S.all(I) then return I;
		end if;
	end loop;
	raise EMPTY_GET;
  exception when CONSTRAINT_ERROR => raise EMPTY_GET;
  end Min;
 
 
  procedure Put(S:in ESET) is -- output set to standard output
    NOT_FIRST:BOOLEAN:=false;
  begin 
    Put('{');
    if not Empty(S)  then
      for I in S.all'range loop 
        if S.all(I) then
		if NOT_FIRST then Put(',');
		end if; 
		NOT_FIRST:=TRUE; Put(I);
        end if;
      end loop;
    end if;
    Put('}');
  end Put;
 
  procedure NORMALIZE(S:in out ESET)is
	dummy:ELEMENT;
  begin
	dummy:=S.all'FIRST; return;
  exception
	when CONSTRAINT_ERROR => S:= new DATA'(ELEMENT=>FALSE);return;
  end NORMALIZE;
 
  procedure Put(I:ELEMENT; INTO:in out ESET) is
  begin NORMALIZE(INTO);
	INTO.all(I):=true;
  end Put;
 
  procedure Getmin(I: out ELEMENT; FROM:in out ESET) is
  	M:ELEMENT:=Min(FROM);
  begin Take(M,FROM); I:=M;
  end Getmin;
 
  procedure Get(I: out ELEMENT; FROM:in out ESET) is
  begin  Getmin(I,FROM);
  end Get;
 
 
  procedure Getmax(I: out ELEMENT; FROM:in out ESET) is
  	M:ELEMENT:=max(FROM);
  begin Take(M,FROM); I:=M;
  end Getmax;
 
  procedure Take(I: ELEMENT; FROM:in out ESET) is
  begin FROM.all(I):=FALSE;
  end Take;
 
end SET_OF;