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var
  f, f1: file of real;
  i, nm: integer;
  k, k1: real;
 
begin
  assign(f, 'tet.dat');
  rewrite(f);
  for i := 1 to 10 do 
  begin
    readln(k);
    write(f, k);
  end;
  close(f);
  reset(f);
  for i := 0 to filesize(f) - 2 do 
  begin
    read(f, k);
    nm := i;
    while not eof(f) do 
    begin
      read(f, k1);
      if k1 > k then begin
        k := k1;
        nm := filepos(f) - 1
      end;    
    end;
    seek(f, i);
    read(f, k1);
    seek(f, nm);
    write(f, k1);
    seek(f, i);
    write(f, k);
  end;  
  close(f);
  assign(f1, 'tttt.dat');
  rewrite(f1);
  reset(f);
  for i := 0 to filesize(f) - 1 do 
  begin
    read(f, k);
    write(f1, k);
  end;
  close(f);
  close(f1);
  reset(f1);
  for i := 0 to filesize(f1) - 1 do 
  begin
    read(f1, k);
    write(k, ' ');
  end;
  close(f1);
end.

var
  f, f1: file;
  i, nm: integer;
  k, k1: real;
 
begin
  assign(F, 'tut.dat');
  rewrite(f, 1);
  for i := 1 to 10 do
  begin
    readln(k);
    blockwrite(f, k, sizeof(real));
  end;
  close(f);
  reset(f, 1);
  for i := 0 to filesize(f) - 2 do
  begin
    blockread(f, k, sizeof(real));
    nm := i;
    while not eof(f) do
    begin
      blockread(f, k1, sizeof(real));
      if k1 > k then begin
        k := k1;
        nm := filepos(f) - 1
      end;
    end;
    seek(f, i);
    blockread(f, k1, sizeof(real));
    seek(f, nm);
    blockwrite(f, k1, sizeof(real));
    seek(f, i);
    blockwrite(f, k, sizeof(real));
  end;
  close(f);
  assign(f1, 'te.dat');
  rewrite(f1, 1);
  reset(f, 1);
  for i := 0 to filesize(f) - 1 do
  begin
    blockread(f, k, sizeof(real));
    blockwrite(f1, k, sizeof(real));
  end;
  close(f);
  close(f1);
  reset(f1, 1);
  for i := 0 to filesize(f1) - 1 do
  begin
    blockread(f1, k, sizeof(real));
    write(k, ' ');
  end;
  close(f1);
end.