PROCEDURE PMGSORT (VAR T:WKFILE ; MAXBLK,F1,F2:INTEGER) ;

 TYPE
   WKFILE = ARRAY[0..2] OF TEXT;
   BLK    = ARRAY[1..500] OF INTEGER;


 VAR
     R,R2:INTEGER;
     BF:ARRAY [1..5] OF INTEGER;
     I,J :INTEGER;
     REW,RES,KEEP:INTEGER;
     FI:ARRAY [0..2] OF INTEGER;
     X:BLK;
 PROCEDURE BSORT(VAR X:BLK);
  var
    i,j,k :integer;
  begin
    for i := 2 to maxblk do
      for j := maxblk downto i do
        if x[j - 1] > x[j] then
          begin
            k := x[j - 1];
            x[j - 1] := x[j];
            x[j] := k
          end
  end;

procedure mgsort(var tape1,tape2,tape3 :text);
  var
    a,b :integer;
  begin
    read(tape1,a);
    read(tape2,b);
    while not(eoln(tape1) or eoln(tape2)) do
      if a < b then
        begin
          write(lst,tape3,a:8);
          read(tape1,a)
        end
      else
        begin
          write(lst,tape3,b:8);
          read(tape2,b)
        end;
    if eoln(tape1) then
      while not eoln(tape2) do
        begin
          write(lst,tape3,b:8);
          read(tape2,b)
        end
    else
      while not eoln(tape1) do
        begin
          write(lst,tape3,a:8);
          read(tape1,a)
        end;
    readln(tape1);
    readln(tape2);
    writeln(lst,tape3,0:8)
  end;

PROCEDURE YOMU (VAR F:TEXT; VAR X:BLK; MAXB :INTEGER);
VAR J :INTEGER;
BEGIN
  FOR J := 1 TO MAXB DO
    BEGIN
      READ(F,X[J]);
      IF EOLN(F) THEN READLN(F)
    END
END;

BEGIN
 REWRITE(T[1]);
 REWRITE(T[2]);
 ASSIGN(T[0],'B:TAPE0.CPM');
 RESET(T[0]);


FOR I := 1 TO F1 DO
 BEGIN
  YOMU(T[0],X,MAXBLK);
  BSORT(X);
  FOR J := 1 TO MAXBLK DO WRITE(T[1],X[J]:8);
  WRITELN(LST,T[1],0:8)
 END;
FOR I := 1 TO F2 DO
 BEGIN
  YOMU(T[0],X,MAXBLK);
  BSORT(X);
  FOR J := 1 TO MAXBLK DO WRITE(T[2],X[J]:8);
  WRITELN(LST,T[2],0:8)
 END;

 REW := 0; RES := 1; KEEP := 2;
 FI[RES] := F1; FI[KEEP] := F2;
 RESET(T[2]);
 REPEAT
  CLOSE(T[REW]);
  CLOSE(T[RES]);
  REWRITE(T[REW]);
  RESET(T[RES]);
  REPEAT
   MGSORT(T[RES],T[KEEP],T[REW])
  UNTIL EOF(T[KEEP]);
 FI[RES]:=FI[RES]-FI[KEEP];
 FI[REW]:=FI[KEEP];
 REW:=(REW+2)MOD 3;
 RES:=(RES+2)MOD 3;
 KEEP:=(KEEP+2)MOD 3;
UNTIL FI[RES]=0;
 FOR R := 0 TO 2 DO CLOSE(T[R])
END;