POJ 2506(放方块）

高精Dp

Program P2506;
type
   arr=record
       a:array[1..10000] of longint;
       len:longint;
       end;
const
   base=1000;
var
   i,j,n:longint;
   f:array[0..250] of arr;
function max(a,b:longint):longint;
begin
   if a<b then exit(b) else exit(a);
end;
Procedure add(a,b:arr;var c:arr);
var
   i,j,len:longint;
begin
   fillchar(c,sizeof(c),0);
   for i:=1 to max(a.len,b.len) do
   begin
      inc(c.a[i],a.a[i]+2*b.a[i]);
      inc(c.a[i+1],c.a[i] div base);
      c.a[i]:=c.a[i] mod base;
   end;
   i:=max(a.len,b.len);
   while (c.a[i+1]>0) do
   begin
      inc(i);
      inc(c.a[i+1],c.a[i] div base);
      c.a[i]:=c.a[i] mod base;
   end;
   while (i>1) and (c.a[i]=0) do dec(i);
   c.len:=i;

end;
begin
   fillchar(f,sizeof(f),0);
   for i:=0 to 250 do f[i].len:=1;
   f[1].a[1]:=1;
   f[0].a[1]:=1;
   for i:=2 to 250 do add(f[i-1],f[i-2],f[i]);
   while not eof do
   begin
      readln(n);
      write(f[n].a[f[n].len]);
      for i:=f[n].len-1 downto 1 do
      begin
         if f[n].a[i]<100 then write('0');
         if f[n].a[i]<10 then write('0');
         write(f[n].a[i]);
      end;
      writeln;
   end;

end.