Shortest path-dijkstra detailed-source code

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Algorithm 6.10 Dijkstra algorithm # include <iostream>using namespace std, #define MAXINT 32767//Represents the maximum value, i.e. ∞ #define MVN              UM 100//MAX vertex number typedef char Vertextype;                  Assume that the data type of the vertex is a character typedef int arctype;                    Assume that the weight of the edge type is int *d=new int[mvnum];          Used to record the shortest short length of bool *s=new bool[mvnum]; Marks whether the vertex enters the S-set int *path=new int[mvnum];//the adjacency matrix of the precursor//------------graph used to record the shortest-path vertex-----------------typedef struct{            Vertextype Vexs[mvnum];      Vertex table Arctype Arcs[mvnum][mvnum];                adjacency Matrix int vexnum,arcnum; The current number of points and sides of the graph}amgraph;int Locatevex (amgraph G, Vertextype v) {//determines the position of Point V in G for (int i = 0; i < g.vexnum; ++i) if (G.vexs[i]   = = v) return i; return-1;}    Locatevexvoid Createudn (amgraph &g) {//using adjacency matrix notation, creating a non-net G int i, J, k;cout << "Please enter the total number of vertices, total number of edges, separated by spaces:";    CIN >> g.vexnum >> g.arcnum;//input total number of vertices, total number of sides cout << endl;cout << "input point name:, such as a" << Endl; for (i = 0; i < G.vexnum; ++i) {cout << "Please enter the name of" << (i+1) << "dot:"; cin >> G.vexs[i];    Input point information}cout << Endl;  for (i = 0; i < g.vexnum; ++i)//Initialize adjacency matrix, the weight of the edge is set to maximum value maxint for (j = 0; j < G.vexnum; ++j) G.arcs[i][j] = MaxInt; cout << "input edge-dependent vertices and weights, such as a B 7" << endl;for (k = 0; k < g.arcnum;++k) {//constructs adjacency matrix Vertextype v1, v2; Arctype w;cout << "Please enter the section" << (k + 1) << "vertices and weights attached to the edge:"; Cin >> v1 >> v2 >> w;//Enter a vertex attached to an edge  And the weighted value i = Locatevex (G, v1); j = Locatevex (G, v2);//determines the position of V1 and V2 in G, that is, the subscript of the vertex array g.arcs[i][j] = w;//Edge <v1, V2> 's weight is set to W g.arcs[j][i] = g.arcs[i][j];// LT;V1, v2> symmetrical edge <v2, v1> with a weight of W}//for}//createudnvoid shortestpath_dij (amgraph G, int v0) {//Dijkstra algorithm for the net g of V0                    The shortest path from vertex to remaining vertex int V, I, W, min;int n = g.vexnum;                  n is the number of vertices in g for (v = 0; v < n; ++v) {//n vertices are initialized sequentially s[v] = false;           S initial empty set d[v] = G.arcs[v0][v]; The shortest path length v0 to each endpoint is initialized to the weighted if on the arc (d[v] < MaxInt) Path [v] = v0;               If there is an arc between V0 and V, the predecessor of V is set to v0 else Path [v] =-1;                    If there is no arc between V0 and V, the predecessor of V is set to 1}//for s[v0]=true;                      Add V0 to S d[v0]=0;         The distance from the source point to the source point is 0/*― initialization ends, the main loop starts, each time the shortest path v0 to a vertex v is evaluated, the V is added to the S set ―*/for (i = 1;i < n; ++i) {//to the remaining n-1 vertices, and then the min= MaxInt is calculated in turn; for (w = 0; w < n; ++w) if (! S[W] && d[w] < min) {//Select a current shortest path with a terminal point of V v = w; min = d[w];}                   if s[v]=true; Add V to s for (w = 0;w < n; ++w)//update from V0 to set v? The shortest path length of all vertices on s if (!   S[W] && (D[v] + g.arcs[v][w] < D[w])) {d[w] = D[v] + g.arcs[v][w];              Update D[w] Path [w] = V;  Change W's precursor to V}//if}//for}//shortestpath_dijvoid displaypath (amgraph G, int begin, int temp) {//Show Shortest path if (path[temp]! = -1) {Displaypath (G, Begin, Path[temp]); cout << G.vexs[path[temp]] << "--";}} Displaypathvoid Main () {cout << "************ algorithm 6.10 Dijkstra algorithm **************" << Endl << Endl; Amgraph G; int I, J, nUm_start, num_destination; Vertextype start, destination; Createudn (g); cout <<endl;cout << "* * * * * No to NET G create complete! "<< endl;for (i = 0; i < G.vexnum; ++i) {for (j = 0; j < G.vexnum; ++j) {if (j! = g.vexnum-1) {if (g.arcs[i ][J]! = MaxInt) cout << g.arcs[i][j] << "\ t", Elsecout << "∞" << "\ T";} Else{if (g.arcs[i][j]! = MaxInt) cout << g.arcs[i][j] <<endl;elsecout << "∞" &LT;&LT;ENDL;}} Forcout << endl;cout << "Please enter start point, end name:"; Cin >> start >> Destination;num_start = Locatevex (G, S Tart); num_destination = Locatevex (G, destination); Shortestpath_dij (g, Num_start), cout << endl << "Shortest path:";D Isplaypath (g, Num_start, num_destination); Cout & lt;< G.vexs[num_destination]<<endl;} Main

Shortest path-dijkstra detailed-source code