谁能告诉我为什么AC不了,是我的思路有问题吗?按照时间排序,从前往后dp,检查下来没啥问题,但是只AC了40%,有没有大佬指教下```const int N = 1e6+5;int f[N];struct Node{int x,y,s,t;};bool cmp(Node &amp;o1,Node &amp;o2){return o1.t < o2.t;}Node node[N];inline int dis(int x1,int y1,int x2,int y2){return abs(x1-x2) + abs(y1-y2);}int main() {int n,m,k;memset(f,0,sizeof f);cin >> n >> m >> k;int ans = 0;for(int i = 0; i < k; i++){cin >> node[i].x >> node[i].y >> node[i].t >> node[i].s;}sort(node,node+k,cmp);for(int i = 0;i < k; i++){if(dis(1,1,node[i].x,node[i].y) <= node[i].t) f[i] = node[i].s;for(int j = 0; j < i; j++){if(dis(node[i].x,node[i].y,node[j].x,node[j].y) <= node[i].t-node[j].t){f[i] = max(f[i],f[j]+node[i].s);}}ans = max(ans,f[i]);}cout << ans << endl;return 0;}```