为啥超时
```cpp
var
f,x,y,t:array[0..10000]of longint;
n,m,i,j,l,ans:longint;
function max(a,b:longint):longint;
begin
if a>b then exit(a);
exit(b);
end;
begin
readln(n,m);
for i:=1 to m do
read(t[i],x[i],y[i]);
for i:=1 to m do
begin
l:=0;
for j:=i-1 downto 1 do
if (t[i]-t[j]>=abs(x[j]-x[i])+abs(y[j]-y[i])) then
l:=max(l,f[j]);
f[i]:=l+1;
ans:=max(ans,f[i]);
end;
write(ans);
end.
```
by bestzzy @ 2017-03-09 16:58:46
用了DP
by bestzzy @ 2017-03-09 17:03:19
@[SSL\_BPT](/space/show?uid=36267)
这里数据加强了，要优化
by lzusa @ 2017-03-09 19:54:45
不知道
by ctz20070818 @ 2017-03-09 20:15:30
学校的不超
by Sakura_nameless @ 2017-03-10 20:58:33
~~(hh)~~
by YZ_DDF @ 2017-08-14 21:31:43
~~假的~~
by YZ_DDF @ 2017-08-14 21:32:15