My alg is 0 1 knapsack, BUT #4 Crash(Access_Violation)!
Need help!

var
a:array[1..100] of longint;
b:array[1..10000] of longint;
max,n,nn,i,s,s2:longint;

procedure readdata;
begin
readln(n);
s:=0;
for i:=1 to n do
begin
read(a[i]);
s:=s+a[i];
end;
s2:=s div 2;
end;

procedure writedata;
begin
writeln(abs( abs(s-max)-abs(max) ));
end;

function check(l:longint):boolean;
var
i:integer;
bb:boolean;

begin
bb:=false;
for i:=1 to nn do
if b[i]=l then
begin
bb:=true;
exit;
end;
check:=false;
end;

procedure sum(l:longint);
var
i,nnn:longint;

begin
nnn:=nn;
for i:=1 to nnn-1 do
begin
if ((b[i]+l)<=s2) and (not check(b[i]+l)) then
begin
if (b[nn]<=s2) and (b[nn]>max) then
max:=b[nn];
inc(nn);
b[nn]:=b[i]+l;
if (b[nn]<=s2) and (b[nn]>max) then
max:=b[nn];
end;
end;
end;

begin
readdata;
nn:=0; max:=a[1];
for i:=1 to n do
begin
if not check(a[i]) then
begin
inc(nn);
b[nn]:=a[i];
if (b[nn]<=s2) and (b[nn]>max) then max:=b[nn];
sum(a[i]);
end;
end;
writedata;
end.

At least AC! Thanks to Allah!
AC!!! 0.001 105 КБ