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program otcht;
type otch=record
grupp:string[20];
pred:string[20];
kol:integer;
pt:integer;
ch:integer;
tr:integer;
dv:integer;
usp:real;
kach:real;
end;
label v;
var   
i,n:integer;
otchet:otch;
f:file of otch;
nomer:integer;
procedure savef ();
begin
writeln('vvedite kolichectvo n:');
readln(n);
rewrite(f); 
for i:=1 to n do begin
writeln('vvedite gruppu, predmet, kolichectvo, pyaterok, chetverok, troek, davoek, uspevaemost, kachestvo:');
readln(otchet.grupp);
readln(otchet.pred);
readln(otchet.kol);
readln(otchet.pt);
readln(otchet.ch);
readln(otchet.tr);
readln(otchet.dv);
otchet.usp:=((otchet.pt+otchet.ch+otchet.tr)/otchet.kol)*100;
otchet.kach:=((otchet.pt+otchet.ch)/otchet.kol)*100;
write(f,otchet); {}
end;
close(f); 
end;
procedure openf; 
begin
reset(f); 
repeat
read(f,otchet);
  write(otchet.grupp:5);
  write(otchet.pred:5);
  write(otchet.kol:5);
  write(otchet.pt:5);
  write(otchet.ch:5);
  write(otchet.tr:5);
  write(otchet.dv:5);
  write('otchet.usp',otchet.usp:2:1);
  write('otchet.kach',otchet.kach:2:1);
  writeln;
  until
  eof(f);
  end;
  procedure oppendf;
  var c:char;{}
  begin
  reset(f);
 
  seek(f,filesize(f));{}
  repeat
  writeln('dobavte zapis:');
  writeln('vvedite  gruppu, predmet, kolichectvo,   pyaterok, chetverok, troek, davoek, uspevaemost,  kachestvo:');
  begin
  readln(otchet.grupp);
  readln(otchet.pred);
  readln(otchet.kol);
  readln(otchet.pt);
  readln(otchet.ch);
  readln(otchet.tr);
  readln(otchet.dv);
  otchet.usp:=((otchet.pt+otchet.ch+otchet.tr)/otchet.kol)*100;
  otchet.kach:=((otchet.pt+otchet.ch)/otchet.kol)*100;
  write(f,otchet); 
  writeln('dla prodolgeniya nagmite y');
  writeln('dla vixoda nsgmite n');
  readln(c);
  end;
  until c<>'y';
  end;
  begin 
   assign(f,'D:\po21\z8\otchet.da'); 
  v:writeln('menu');
   writeln('1.sozdanie faila:');
  writeln('2.chtenie iz faila:');
  writeln('3.dobavlenie zapisey:');
  writeln('4. voxos iz programmi:');
  writeln('vibrat nomer faila:');
  readln(nomer);
  case nomer of 
  1:Savef;
  2:Openf;
  3:oppendf;
  4:exit;
  end;
 goto v; 
  readln;
  end.