hdu2112 dijkstra

题目链接：http://icpc.njust.edu.cn/Problem/Hdu/2112/

只要需处理一下字符串，给他个编号再跑一半dijkstra就行。

代码如下：

 #include<bits/stdc++.h>
 using namespace std;
 typedef unsigned int ui;
 typedef long long ll;
 typedef unsigned long long ull;
 #define pf printf
 #define mem(a,b) memset(a,b,sizeof(a))
 #define prime1 1e9+7
 #define prime2 1e9+9
 #define pi 3.14159265
 #define lson l,mid,rt<<1
 #define rson mid+1,r,rt<<1|1
 #define scand(x) scanf("%llf",&x)
 #define f(i,a,b) for(int i=a;i<=b;i++)
 #define scan(a) scanf("%d",&a)
 #define mp(a,b) make_pair((a),(b))
 #define P pair<int,int>
 #define dbg(args) cout<<#args<<":"<<args<<endl;
 #define inf 0x3f3f3f3f
 const int maxn=;
 int n,m,t;
 char st[maxn],ed[maxn],num[][maxn];
 int edge[maxn][maxn],d[maxn];
 int cnt=;
 int find(char* s)
 {
     if(cnt==)
     {
         strcpy(num[],s);
         cnt=;
         return ;
     }
     f(i,,cnt-)
     {
         if(strcmp(s,num[i])==)return i;
     }
     strcpy(num[cnt],s);
     cnt++;
     return cnt-;
 }
 void init()
 {
     cnt=;
     mem(edge,inf);
 }
 void dijkstra(int src)
 {
     f(i,,cnt-)d[i]=inf;
     d[src]=;
     priority_queue<P,vector<P>,greater<P> >q;
     q.push(mp(,src));
     while(!q.empty())
     {
         P now=q.top();
         q.pop();
         int u=now.second;
         if(d[u]<now.first)continue;
         f(i,,cnt-)
         {
             if(edge[u][i]!=inf&&d[i]>d[u]+edge[u][i])
             {
                 d[i]=d[u]+edge[u][i];
                 q.push(mp(d[i],i));
             }
         }
     }
 }
 int main()
 {
     //freopen("input.txt","r",stdin);
     //freopen("output.txt","w",stdout);
     std::ios::sync_with_stdio(false);
     while(scan(n))
     {
         if(n==-)break;
         init();
         scanf("%s",st);
         int s=find(st);
         scanf("%s",ed);
         int e=find(ed);
         int a,b,w;
         f(i,,n)
         {
             scanf("%s%s%d",&st,&ed,&w);
             a=find(st);
             b=find(ed);
             if(edge[a][b]>w)edge[a][b]=edge[b][a]=w;//注意这是一个无向图
         }
         dijkstra(s);
         if(d[e]!=inf)
         pf("%d\n",d[e]);
         else pf("-1\n");
      }
  }