请大牛帮忙看看，哪里错了？？？

var

i,j,k,l,m,n,h:integer;

a,b:array[1..100]of integer;

begin

read(n);

for i:=1 to n do

begin

read(a[i]);

b[i]:=a[i];

end;

for i:=1 to n do

for j:=i+1 to n do

begin

if a[i]=b[j] then b[j]:=0;

end;

for i:=1 to n do

if b[i]=0 then begin

for m:=i to n do begin

a[m]:=a[m+1];

b[m]:=b[m+1];

end;

n:=n-1;

end;

k:=n;

writeln(k);

for i:=1 to k do

for j:=i to k do

begin

if a[i]>a[j] then

begin

h:=a[i];

a[i]:=a[j];

a[j]:=h;

end;

end;

for i:=1 to k do

write(a[i],' ');

readln;

end.