07-图6 旅游规划 (25 分) 

  1 #include <cstdio>
  2 #include <stdlib.h>
  3 const int INFINITY = 65536;
  4 const int MaxVertexNum = 501;
  5 const int ERROR = -1;
  6 int dist[MaxVertexNum], path[MaxVertexNum], collected[MaxVertexNum],fare[MaxVertexNum];
  7 typedef int Vertex;
  8 typedef int WeightType;
  9 
 10 typedef struct GNode * MGraph;
 11 struct GNode {
 12     int Nv;
 13     int Ne;
 14     WeightType G[MaxVertexNum][MaxVertexNum];
 15     WeightType F[MaxVertexNum][MaxVertexNum];
 16 };
 17 
 18 
 19 
 20 Vertex FindMinDist( MGraph Graph )
 21 { /* 返回未被收录顶点中dist最小者 */
 22     Vertex MinV, V;
 23     int MinDist = INFINITY;
 24     
 25     for (V=0; V<Graph->Nv; V++) {
 26         if ( collected[V]==false && dist[V]<MinDist) {
 27             /* 若V未被收录，且dist[V]更小 */
 28             MinDist = dist[V]; /* 更新最小距离 */
 29             MinV = V; /* 更新对应顶点 */
 30         }
 31     }
 32     if (MinDist < INFINITY) /* 若找到最小dist */
 33         return MinV; /* 返回对应的顶点下标 */
 34     else return ERROR;  /* 若这样的顶点不存在，返回错误标记 */
 35 }
 36 
 37 
 38 
 39 void init(MGraph Graph)
 40 {
 41     Vertex V;
 42     for( V=0; V<Graph->Nv; V++) {
 43 
 44         fare[V] = INFINITY;
 45     }
 46 }
 47 
 48 bool Dijkstra( MGraph Graph, Vertex S )
 49 {
 50     
 51     Vertex V, W;
 52     
 53     /* 初始化：此处默认邻接矩阵中不存在的边用INFINITY表示 */
 54     for ( V=0; V<Graph->Nv; V++ ) {
 55         dist[V] = Graph->G[S][V];
 56         fare[V] = Graph->F[S][V];
 57         if ( dist[V]<INFINITY )
 58             path[V] = S;
 59         else
 60             path[V] = -1;
 61         collected[V] = false;
 62     }
 63     
 64     /* 先将起点收入集合 */
 65     dist[S] = 0;
 66     collected[S] = true;
 67     
 68     while (1) {
 69         /* V = 未被收录顶点中dist最小者 */
 70         V = FindMinDist( Graph );
 71         if ( V==ERROR ) /* 若这样的V不存在 */
 72             break;      /* 算法结束 */
 73         collected[V] = true;  /* 收录V */
 74         for( W=0; W<Graph->Nv; W++ ) /* 对图中的每个顶点W */
 75         /* 若W是V的邻接点并且未被收录 */
 76             if ( collected[W]==false && Graph->G[V][W]<INFINITY ) {
 77                 
 78                 if ( Graph->G[V][W]<0 ) /* 若有负边 */
 79                     return false; /* 不能正确解决，返回错误标记 */
 80                 
 81                 /* 若收录V使得dist[W]变小 */
 82                 if ( dist[V]+Graph->G[V][W] < dist[W]) {
 83                     dist[W] = dist[V]+Graph->G[V][W]; /* 更新dist[W] */
 84                     path[W] = V; /* 更新S到W的路径 */
 85                     fare[W] = fare[V]+Graph->F[V][W];
 86                 }
 87                 else if(dist[V]+Graph->G[V][W] == dist[W] and fare[V] + Graph->F[V][W] < fare[W] ) {
 88                     path[W] = V; /* 更新S到W的路径 */
 89                     fare[W] = fare[V]+Graph->F[V][W];
 90                 }
 91             }
 92     } /* while结束*/
 93     return true; /* 算法执行完毕，返回正确标记 */
 94 }
 95 
 96 
 97 MGraph buildGraph(int Nv, int Ne)
 98 {
 99     int S, E, len, fees;
100     
101     MGraph Graph = (MGraph) malloc(sizeof(struct GNode));
102     //init
103     Graph->Nv = Nv;
104     Graph->Ne = Ne;
105     for(int i=0; i<Nv; i++) {
106         for(int j=0; j<Nv; j++) {
107             Graph->G[i][j] = INFINITY;
108             Graph->F[i][j] = INFINITY;
109         }
110     }
111     
112     for(int i=0; i<Ne; i++) {
113         scanf("%d %d %d %d", &S, &E, &len, &fees);
114         Graph->G[S][E] = len;
115         Graph->G[E][S] = len;
116         Graph->F[E][S] = fees;
117         Graph->F[S][E] = fees;
118     }
119     return Graph;
120 }
121 
122 int main()
123 {
124     int N, M, S, D;
125     scanf("%d%d%d%d", &N, &M, &S, &D);
126     
127     MGraph Graph = buildGraph(N, M);
128 
129     Dijkstra(Graph, S);
130     
131     printf("%d %d\n", dist[D], fare[D]);
132     
133 }
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posted @ 2019-05-28 10:35  Acoccus  阅读(257)  评论(0)    收藏  举报