Breadth-first traversal and depth-first traversal of graphs

Graph is a very important data structure, which is widely used in our programming life.

#include <iostream>using namespacestd;#defineINFINITY 32767#defineMax_vex 20//maximum number of vertices#defineQueue_size (max_vex+1)//Queue LengthBOOL*visited;//array of Access flags//the adjacency matrix storage structure of graphstypedefstruct{    Char*vexs;//vertex Vector    intArcs[max_vex][max_vex];//adjacency Matrix    intVexnum,arcnum;//the current number of vertices and arcs of the graph}graph;//Queue classclassqueue{ Public:    voidInitqueue () {Base=(int*)malloc(queue_size*sizeof(int)); Front=rear=0; }    voidEnQueue (inte) {Base[rear]=e; Rear= (rear+1)%queue_size; }    voidDeQueue (int&e) {e=Base[Front]; Front= (front+1)%queue_size; } Public:    int*Base; intFront; intrear;};//find the position of element C in Figure GintLocate (Graph G,Charc) {     for(intI=0; i<g.vexnum;i++)        if(g.vexs[i]==c)returni; return-1;}//Create a network without a directionvoidCreateudn (Graph &G) {    inti,j,w,s1,s2; Chara,b,temp; cout<<"Enter the number of vertices and number of arcs:"; CIN>>G.vexnum>>G.arcnum; G.vexs=(Char*)malloc(g.vexnum*sizeof(Char));//number of assigned verticescout<<"input"<<G.vexnum<<"a vertex."<<Endl;  for(i=0; i<g.vexnum;i++)    {         //initializing verticescout<<"input vertices"<<i+1<<":"; CIN>>G.vexs[i]; }     for(i=0; i<g.vexnum;i++)//initializing adjacency matrices         for(j=0; j<g.vexnum;j++) G.arcs[i][j]=INFINITY; cout<<"input"<<G.arcnum<<"arc."<<Endl;  for(i=0; i<g.arcnum;i++)    {         //Initialize Arccout<<"Input Arc"<<i+1<<":"; CIN>>a>>b>>w;//enter vertices and weights attached to an edges1=Locate (g,a); S2=Locate (G,B); G.ARCS[S1][S2]=g.arcs[s2][s1]=W; }}//the first adjacency vertex of vertex k in Figure GintFirstvex (Graph G,intk) {    if(k>=0&& k<g.vexnum) {//K Reasonable         for(intI=0; i<g.vexnum;i++)            if(g.arcs[k][i]!=INFINITY)returni; }    return-1;}//The next adjacency vertex of the first J adjacency Vertex of vertex i in Figure gintNextvex (Graph G,intIintj) {    if(i>=0&& I<g.vexnum && j>=0&& j<g.vexnum) {//I,j Reasonable         for(intk=j+1; k<g.vexnum;k++)            if(g.arcs[i][k]!=INFINITY)returnK; }    return-1;}//Depth-First traversalvoidDFS (Graph G,intk) {    inti; if(k==-1)    {         //The first time Dfs is executed, K is-1         for(i=0; i<g.vexnum;i++)            if(!Visited[i]) DFS (G,i); //call Dfs on a vertex that has not been accessed    }    Else{Visited[k]=true; cout<<G.vexs[k];//Access to the K-vertex         for(I=firstvex (g,k); i>=0; i=Nextvex (g,k,i))if(!Visited[i]) DFS (G,i); //The unreachable adjacency vertex i for K recursively calls Dfs    }}//breadth-First traversalvoidBFS (Graph G) {intK; Queue Q; //Auxiliary Queue QQ.initqueue ();  for(intI=0; i<g.vexnum;i++)        if(!Visited[i]) {             //I have not yet visitedvisited[i]=true; cout<<G.vexs[i]; Q.enqueue (i); //I into row             while(q.front!=q.rear) {q.dequeue (k);//team head element is dequeue and set to K                 for(intW=firstvex (g,k); w>=0; w=Nextvex (g,k,w))if(!Visited[w]) {                         //The unreachable adjacency vertex of W is Kvisited[w]=true; cout<<G.vexs[w];                    Q.enqueue (w); }            }        }}//Main functionintMain () {inti;    Graph G;    CREATEUDN (G); Visited=(BOOL*)malloc(g.vexnum*sizeof(BOOL)); cout<<"Depth-First traversal:";  for(i=0; i<g.vexnum;i++) Visited[i]=false; DFS (G,-1); cout<<"\ n Breadth-first traversal:";  for(i=0; i<g.vexnum;i++) Visited[i]=false;    BFS (G); System ("Pause"); return 0;}

Breadth-first traversal and depth-first traversal of graphs