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：

 1 #include<bits/stdc++.h>
 2 using namespace std;
 3 typedef unsigned int ui;
 4 typedef long long ll;
 5 typedef unsigned long long ull;
 6 #define pf printf
 7 #define mem(a,b) memset(a,b,sizeof(a))
 8 #define prime1 1e9+7
 9 #define prime2 1e9+9
10 #define pi 3.14159265
11 #define lson l,mid,rt<<1
12 #define rson mid+1,r,rt<<1|1
13 #define scand(x) scanf("%llf",&x) 
14 #define f(i,a,b) for(int i=a;i<=b;i++)
15 #define scan(a) scanf("%d",&a)
16 #define mp(a,b) make_pair((a),(b))
17 #define P pair<int,int>
18 #define dbg(args) cout<<#args<<":"<<args<<endl;
19 #define inf 0x3f3f3f3f
20 const int maxn=200;
21 int n,m,t;
22 char st[maxn],ed[maxn],num[10005][maxn];
23 int edge[maxn][maxn],d[maxn];
24 int cnt=0;
25 int find(char* s)
26 {
27     if(cnt==0)
28     {
29         strcpy(num[0],s);
30         cnt=1;
31         return 0;
32     }
33     f(i,0,cnt-1)
34     {
35         if(strcmp(s,num[i])==0)return i;
36     }
37     strcpy(num[cnt],s);
38     cnt++;
39     return cnt-1;
40 }
41 void init()
42 {
43     cnt=0;
44     mem(edge,inf);
45 }
46 void dijkstra(int src)
47 {
48     f(i,0,cnt-1)d[i]=inf;
49     d[src]=0;
50     priority_queue<P,vector<P>,greater<P> >q;
51     q.push(mp(0,src));
52     while(!q.empty())
53     {
54         P now=q.top();
55         q.pop();
56         int u=now.second;
57         if(d[u]<now.first)continue;
58         f(i,0,cnt-1)
59         {
60             if(edge[u][i]!=inf&&d[i]>d[u]+edge[u][i])
61             {
62                 d[i]=d[u]+edge[u][i];
63                 q.push(mp(d[i],i));
64             }
65         }
66     }
67 }
68 int main()
69 {
70     //freopen("input.txt","r",stdin);
71     //freopen("output.txt","w",stdout);
72     std::ios::sync_with_stdio(false);
73     while(scan(n))
74     {    
75         if(n==-1)break;
76         init();
77         scanf("%s",st);
78         int s=find(st);
79         scanf("%s",ed);
80         int e=find(ed);
81         int a,b,w;
82         f(i,1,n)
83         {
84             scanf("%s%s%d",&st,&ed,&w);
85             a=find(st);
86             b=find(ed);
87             if(edge[a][b]>w)edge[a][b]=edge[b][a]=w;//注意这是一个无向图 
88         }
89         dijkstra(s);
90         if(d[e]!=inf)
91         pf("%d\n",d[e]);
92         else pf("-1\n");
93      } 
94  }