hdu 4725 The Shortest Path in Nya Graph （最短路 两种做法 1.建图+SPFA 2.建图+优先队列+Dijkstra）

The Shortest Path in Nya GraphTime Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 1235    Accepted Submission(s): 274

Problem DescriptionInputOutputSample InputSample OutputSource#include <iostream>#include <cstdio>#include <cstring>#include <queue>#define maxn 200005#define INF 0x3f3f3f3fusing namespace std;int n,m,c,ans,cnt;bool vis[maxn],vv[maxn];int dist[maxn],pp[maxn],lay[maxn];struct node{ int pos,dd; bool operator <(const node&xx)const { return dd>xx.dd; }}cur,now;struct Node{ int v,w; int next;} edge[20*maxn];priority_queue<node>q;void init(){ memset(pp,0,sizeof(pp)); memset(vv,0,sizeof(vv)); memset(dist,0x3f,sizeof(dist));}void addedge(int u,int v,int w){ cnt++; edge[cnt].v=v; edge[cnt].w=w; edge[cnt].next=pp[u]; pp[u]=cnt;}void Dijkstra(){ int i,j,u,v,w; memset(vis,0,sizeof(vis)); while(!q.empty()) q.pop(); dist[1]=0; cur.pos=1,cur.dd=0; q.push(cur); while(!q.empty()) { now=q.top(); q.pop(); u=now.pos; if(vis[u]) continue ; vis[u]=1; for(i=pp[u]; i; i=edge[i].next) { v=edge[i].v; w=edge[i].w; if(!vis[v]&&dist[v]>dist[u]+w) { dist[v]=dist[u]+w; cur.pos=v,cur.dd=dist[v]; q.push(cur); } } }}int main(){ int i,j,t,u,v,w,test=0; scanf("%d",&t); while(t--) { scanf("%d%d%d",&n,&m,&c); init(); cnt=0; for(i=1; i<=n; i++) { scanf("%d",&u); lay[i]=u; vv[u]=1; } for(i=1; i<n; i++) { if(vv[i]&&vv[i+1]) { addedge(n+i,n+i+1,c); addedge(n+i+1,n+i,c); } } for(i=1; i<=n; i++) { addedge(n+lay[i],i,0); if(lay[i]>1) addedge(i,n+lay[i]-1,c); if(lay[i]<n) addedge(i,n+lay[i]+1,c); } for(i=1; i<=m; i++) { scanf("%d%d%d",&u,&v,&w); addedge(u,v,w); addedge(v,u,w); } Dijkstra(); printf("Case #%d: ",++test); ans=dist[n]; if(ans<INF) printf("%d\n",ans); else printf("-1\n"); } return 0;}