poj 1158

最短路的应用，只不过路径的权值从单一的长度变成了各种耗费时间的和

#include <iostream>#include <cstdio>#include <string.h>using namespace std;const int maxn=300+10;const int maxm=(50000+10)*2;const int inf=200000000;int head[maxn],dis[maxn],vis[maxn],pre[maxn],re[maxn],ans[maxn];int e[maxm],nextv[maxm],cost[maxm],loc[maxm];int s,t,n,m;struct node{char c;intr,tb,tp;};struct color{char c;int r;};node light[maxn];int min(int a,int b) { return a<b?a:b; }color getCol(int y, int time) {     color tem; int did=light[y].r-time;     if(did>0)     {         tem.c=light[y].c;         tem.r=did;     } else  { did=-did; did=did%(light[y].tb+light[y].tp); if(light[y].c=='B') { if(did<light[y].tp) { tem.c='P'; tem.r=light[y].tp-did; } else { tem.c='B'; tem.r=light[y].tb-(did-light[y].tp); } } else  { if(did<light[y].tb) { tem.c='B'; tem.r=light[y].tb-did; } else  { tem.c='P'; tem.r=light[y].tp-(did-light[y].tb); } } } return tem; }int getT(int from,int to,int time,int flag){if(flag>2) return -1;color c1=getCol(from,time),c2=getCol(to,time);if(c1.c==c2.c) return time;else if(c1.r==c2.r)  return getT(from,to,time+c1.r,flag+1);else return time+min(c1.r,c2.r);}void dijkstra(){int i,j;for(i=1;i<=n;i++){dis[i]=inf; vis[i]=0;}dis[s]=0;for(i=1;i<=n;i++){int midv=inf,x=-1;for(j=1;j<=n;j++){if(!vis[j]&&dis[j]<midv) midv=dis[x=j];}if(x==-1||x==t) return;vis[x]=1;for(j=head[x];j!=-1;j=nextv[j]){int y=loc[j];if(!vis[y]){int tem=getT(x,y,dis[x],0);if(tem==-1) continue;else {tem+=cost[j];if(tem<dis[y]){dis[y]=tem;pre[y]=x;}}}}}}void print(int tem){int i=tem;int tot=0;while(i!=s){ans[tot++]=i;i=pre[i];}printf("%d ",s);if(tot>=1) for(i=tot-1;i>=0;i--) printf("%d ",ans[i]);}int main(){while(~scanf("%d%d",&s,&t)){scanf("%d%d",&n,&m);getchar();int i;char tc;for(i=1;i<=n;i++) {scanf("%c%d%d%d",&light[i].c,&light[i].r,&light[i].tb,&light[i].tp);getchar();}memset(head,-1,sizeof(head));int u,v,ti;int tot=0;for(i=1;i<=m;i++) {scanf("%d%d%d",&u,&v,&ti);loc[tot]=v;nextv[tot]=head[u];head[u]=tot;cost[tot]=ti;tot++;loc[tot]=u;nextv[tot]=head[v];head[v]=tot;cost[tot]=ti;tot++;}dijkstra();if(dis[t]==inf) printf("0\n");else{printf("%d\n",dis[t]);//print(pre[t]);//printf("%d\n",t);}}return 0;}