HDU 3790 最短路径问题（SPFA || Dijkstra ）

题意：中文题不详述。
思路：无论是SPFA还是Dijkstra都在更新最短路的那个地方直接将花费更新了就行，还有别忘了判重边，话说因为忘了判重边WA了一次。
 1 //3790
 2 #include <iostream>
 3 #include <cstdio>
 4 #include <cstring>
 5 #include <algorithm>
 6 #include <queue>
 7 const int INF = 1 << 28 ;
 8 
 9 using namespace std;
10 
11 int n, m,s,t;
12 int cost[1100][1100] ,mapp[1100][1010];
13 int dist[1100],cost1[1100] ;
14 int vis[1100] ;
15 
16 void spfa(int src)
17 {
18     queue<int> Q ;
19     memset(vis,0,sizeof(vis)) ;
20     for(int i = 1 ; i <= n ; i++)
21     {
22         dist[i] = INF ;
23         cost1[i] = INF ;
24     }
25     dist[src] = 0 ;
26     vis[src] = 1 ;
27     cost1[src] = 0;
28     Q.push(src) ;
29     while(!Q.empty())
30     {
31         int u = Q.front() ;
32         Q.pop() ;
33         vis[u] = 0;
34         for(int i = 1 ; i <= n ; i++)
35         {
36 
37             if(dist[i] > dist[u] + mapp[u][i])
38             {
39                 dist[i] = dist[u] + mapp[u][i] ;
40                 cost1[i] = cost1[u] + cost[u][i] ;
41                 if(!vis[i])
42                 {
43                     vis[i] = 1 ;
44                     Q.push(i) ;
45                 }
46             }
47             else if(dist[i] == dist[u]+mapp[u][i])
48             {
49                 if(cost1[i] > cost1[u] + cost[u][i])
50                 {
51                     cost1[i]=cost1[u] + cost[u][i];
52                     if(!vis[i])
53                     {
54                         vis[i] = 1 ;
55                         Q.push(i) ;
56                     }
57                 }
58 
59             }
60         }
61     }
62 }
63 void Init()
64 {
65     for(int i = 1 ; i <= n ; i++)
66         for(int j = 1 ; j <= n ; j++)
67         {
68             if(i == j) mapp[i][j] = cost[i][j] = 0 ;
69             else mapp[i][j] = cost[i][j] = INF ;
70         }
71 }
72 int main()
73 {
74     //
75     while(cin >> n >> m)
76     {
77         if(n == 0 && m == 0) break ;
78         int a, b , d , p ;
79         Init() ;
80         for(int i = 0 ; i < m ; i++)
81         {
82             cin >> a >> b >> d >> p ;
83             if(mapp[a][b] > d)
84             {
85                 mapp[a][b] = mapp[b][a] = d ;
86                 cost[a][b] = cost[b][a] = p ;
87             }
88             else if(mapp[a][b] == d&&cost[a][b] > p)
89                 cost[a][b] = cost[b][a] = p ;
90         }
91         cin >> s >> t ;
92         spfa(s) ;
93         printf("%d %d\n",dist[t],cost1[t]) ;
94     }
95     return 0;
96 }
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