记录编号	5932	评测结果	AAAAAAAAAA
题目名称	[LOL2000] 回文词	最终得分	100
用户昵称	name:弓虽	是否通过	通过
代码语言	Pascal	运行时间	4.611 s
提交时间	2008-10-29 17:46:37	内存使用	95.57 MiB

program palin(input,output);
 var
  i,j,k:longint;
  n:longint;
  ans:longint;
  a:array [0..5001,0..5001] of longint;
  z,d:array [1..5000] of char;
 function max(x,y:longint):longint;
  begin
   if x>y then max:=x
   else max:=y;
   end;
begin
 assign(input,'palin.in');
 assign(output,'palin.out');
 reset(input);
 rewrite(output);
 readln(n);
  for i := 1 to n do
   read(z[i]);
   readln;
 k:=n;
  for j:=1 to n do begin
   d[j]:=z[k];
   k:=k-1;
   end;
a[0,0]:=0;
  for i:=1 to n do
   for j:=1 to n do
    begin
     if z[i]=d[j] then a[i,j]:=a[i-1,j-1]+1;
      if z[i]<>d[j] then a[i,j]:=max(a[i-1,j],a[i,j-1]);
 end;
 ans:=n-a[n,n];
 writeln(ans);
 close(input);
 close(output);

end.