Android中Service机制基础广播的类型：标准广播（高效，无法截断）、有序广播（同步执行，可以截断，有先后顺序）接收系统广播动态注册监听系统广播BroadcastReceiver的创建方法：新建一个类，让它继承自BroadcastReceiver，并重写父类的onReceive()方法。书上的示例，监听系统时间变化的广播，显示通

地铁图 原始数据共250个站点,或有遗漏1苹果园,39.9263251384,116.17778062822古城,39.9072014648,116.19024753573八角游乐园,39.9074319023,116.21282100684八宝山,39.9072673042,116.23582363135玉泉路,39.9073331435,116.25303268436五棵松,39.

最短路负环判断#include<bits/stdc++.h>usingnamespacestd;structnode{intfrom,to,v;}edge[100005];#defineoo2000000000intdis[100005];intmain(){intn,m,s,t;cin>>n>>m>>s>>t;for(inti=1;i<=m;i++){