记录编号	39450	评测结果	AAAAAAAAAAAAAAA
题目名称	路由器	最终得分	100
用户昵称	isabella	是否通过	通过
代码语言	Pascal	运行时间	0.317 s
提交时间	2012-07-11 17:09:22	内存使用	1.79 MiB

type
 point=^node;
 node=record
  data:longint;
  next:point;
  end;
var
 f,g:array[1..100000]of longint;
 ch,map:array[1..100000]of point;
 v:array[1..100000]of boolean;
 i,j,n,k,a,b,ans:longint;
 p:point;

procedure make(x:longint);
 var p,po:point;
 begin
  v[x]:=true;
  p:=map[x];
  while p<>nil do
   begin
    if v[p^.data]=false then
     begin new(po);po^.data:=p^.data;
      po^.next:=ch[x];ch[x]:=po;
     end;
    p:=p^.next;
   end;
  p:=ch[x];
  while p<>nil do
   begin make(p^.data);p:=p^.next;end;
 end;

procedure dp(x:longint);
 var p:point;
     m2,m1:longint;
 begin
  p:=ch[x];
  if p=nil then
   begin
    f[x]:=0;g[x]:=1;exit;
   end;

  while p<>nil do
   begin dp(p^.data);p:=p^.next;end;
  m1:=0;m2:=0;
  p:=ch[x];
  while p<>nil do
   begin
     if f[p^.data]>m1 then m1:=f[p^.data];
     if g[p^.data]>m2 then m2:=g[p^.data];
     p:=p^.next;
   end;
  if m2>=k then
   begin ans:=ans+1;f[x]:=k;g[x]:=0;exit;end;
  if (m1-1)>=m2 then
   begin f[x]:=m1-1;g[x]:=0;exit;end;
  g[x]:=m2+1;f[x]:=m1-1;
 end;

begin
assign(input,'routea.in');reset(input);
assign(output,'routea.out');rewrite(output);
 readln(n,k);
 if k=0 then begin
  writeln(n);close(input);close(output);halt;
  end;
 for i:=1 to n-1 do
  begin
   readln(a,b);
   new(p);p^.data:=b;p^.next:=map[a];map[a]:=p;
   new(p);p^.data:=a;p^.next:=map[b];map[b]:=p;
  end;
 fillchar(v,sizeof(v),0);
 make(1);
 {for i:=1 to n do
  begin
   p:=ch[i];
   while p<>nil do
    begin
     write(p^.data,' ');
     p:=p^.next;
    end;
   writeln;
  end; }
 ans:=0;
 dp(1);  //for i:=1 to n do writeln(f[i],' ',g[i]);
 if g[1]>0 then writeln(ans+1) else writeln(ans);
close(input);close(output);
end.