program ural1138;
  var
    i,ans,n,s:integer;
    f:array[1..10000] of integer;

procedure dp;
  var i,j:integer;
  begin
    f[s]:=1;
    for i:=s to n-1 do
     for j:=1 to 100 do
      if ((i*j) mod 100=0)and(i+(i*j) div 100<=n)
       then if f[i]+1>f[i+(i*j) div 100]
       then f[i+(i*j) div 100]:=f[i]+1
  end;

begin
  readln(n,s);
  dp;
  ans:=0;
  for i:=n downto s do if f[i]>ans then ans:=f[i];
  writeln(ans)
end.

add these:
  "if f[i]>0 then......"

Thanks.
I make a mistake here,too.

many thanks,
mistake here too