uses crt;
var n,i,j,kt,m:longint; a:array[1..100000000]of longint;
begin
clrscr;
write('n=');readln(n);
for i:=1 to n do
begin
write('a[',i,']=');readln(a[i]);
end;
for i:=1 to n do
begin
kt:=0;
for j:=1 to n do if i=a[j] then kt:=1;
if kt=0 then write(i,'; ') else inc(m);
end;
if m=n then writeln('Khong co so nao khong thuoc day!');
readln
end.
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